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mirror of https://github.com/switchbrew/libnx.git synced 2025-07-26 03:52:24 +02:00
libnx/nx/source/runtime/resolver.c
fincs 26f620dc0e
Split up socket.c + work in progress changes:
- DNS stuff moved to runtime/resolver.c & .h
- Address manipulation functions moved to runtime/util/inet_addr.c
- Removed sfdnsres/nifm handling in runtime/devices/socket.c
- Renamed socketGetLastBsdResult to socketGetLastResult
- Renamed socketGetLastSfdnsresResult to resolverGetLastResult
- gethostid now inits/deinits nifm as needed
- sfdnsres related configuration gone from SocketInitConfig
- Fixed bug in addrinfo deserialization
- getaddrinfo rewritten, hints can now be NULL
- TODO: add back a way to control service discovery/cancel handle
2019-10-28 12:36:29 +01:00

578 lines
18 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include "result.h"
#include "services/sfdnsres.h"
#include "services/nifm.h"
#include "runtime/resolver.h"
__thread int h_errno;
static __thread Result g_resolverResult;
static size_t g_resolverHostByNameBufferSize = 0x200; // ResolverOptionLocalKey::GetHostByNameBufferSizeUnsigned64
static size_t g_resolverHostByAddrBufferSize = 0x200; // ResolverOptionLocalKey::GetHostByAddrBufferSizeUnsigned64
static size_t g_resolverAddrInfoBufferSize = 0x1000; // ResolverOptionLocalKey::GetAddrInfoBufferSizeUnsigned64
static size_t g_resolverAddrInfoHintsBufferSize = 0x400; // ResolverOptionLocalKey::GetAddrInfoHintsBufferSizeUnsigned64
Result resolverGetLastResult(void) {
return g_resolverResult;
}
static struct hostent *_resolverDeserializeHostent(int *err, const void *out_he_serialized) {
const char *buf = (const char *)out_he_serialized;
const char *pos, *pos_aliases, *pos_addresses;
size_t name_size, total_aliases_size = 0;
size_t nb_addresses;
size_t nb_aliases = 0;
size_t nb_pos;
size_t len;
int addrtype, addrlen;
struct hostent *he;
// Calculate the size of the buffer to allocate
pos = buf;
name_size = strlen(pos) + 1;
pos += name_size;
nb_aliases = ntohl(*(const u32 *)pos);
pos += 4;
pos_aliases = pos;
if(nb_aliases>0) {
for(nb_pos=0, len = 1; nb_pos<nb_aliases; nb_pos++, pos += len + 1) {
len = strlen(pos);
}
}
total_aliases_size = pos - pos_aliases;
// Nintendo uses unsigned short here...
addrtype = htons(*(const u16 *)pos);
pos += 2;
addrlen = htons(*(const u16 *)pos);
pos += 2;
// sfdnsres will only return IPv4 addresses for the "host" commands
if(addrtype != AF_INET || addrlen != sizeof(struct in_addr)) {
*err = NO_ADDRESS;
return NULL;
}
// The official hostent (de)serializer doesn't support IPv6, at least not currently.
nb_addresses = ntohl(*(const u32 *)pos);
pos += 4;
pos_addresses = pos;
pos += addrlen * nb_addresses;
he = (struct hostent *)malloc(
sizeof(struct hostent)
+ name_size
+ 8 * (nb_aliases + 1 + nb_addresses + 1)
+ total_aliases_size
+ addrlen * nb_addresses
);
if(he == NULL) {
*err = NO_RECOVERY;
return NULL;
}
if (name_size == 1) {
he->h_name = NULL;
he->h_aliases = (char**)((char*)he + sizeof(struct hostent));
}
else {
he->h_name = (char*)he + sizeof(struct hostent);
memcpy(he->h_name, buf, name_size);
he->h_aliases = (char **)(he->h_name + name_size);
}
he->h_addrtype = addrtype;
he->h_length = addrlen;
he->h_addr_list = he->h_aliases + nb_aliases + 1;
if(nb_aliases>0) {
char *alias = (char *)(he->h_addr_list + nb_addresses + 1);
memcpy(alias, pos_aliases, total_aliases_size);
for(size_t i = 0; i < nb_aliases; i++) {
he->h_aliases[i] = alias;
alias += strlen(alias) + 1;
}
}
he->h_aliases[nb_aliases] = NULL;
if(nb_addresses>0) {
struct in_addr *addresses = (struct in_addr *)(he->h_addr_list + nb_addresses + 1 + total_aliases_size);
memcpy(addresses, pos_addresses, addrlen * nb_addresses);
for(size_t i = 0; i < nb_addresses; i++) {
he->h_addr_list[i] = (char *)&addresses[i];
addresses[i].s_addr = ntohl(addresses[i].s_addr); // lol Nintendo
}
}
he->h_addr_list[nb_addresses] = NULL;
return he;
}
struct addrinfo_serialized_hdr {
u32 magic;
int ai_flags;
int ai_family;
int ai_socktype;
int ai_protocol;
u32 ai_addrlen;
};
static size_t _resolverSerializeAddrInfo(struct addrinfo_serialized_hdr *hdr, const struct addrinfo *ai) {
size_t subsize1 = (ai->ai_addr == NULL || ai->ai_addrlen == 0) ? 4 : ai->ai_addrlen; // not posix-compliant ?
size_t subsize2 = ai->ai_canonname == NULL ? 1 : (strlen(ai->ai_canonname) + 1);
hdr->magic = htonl(0xBEEFCAFE); // Seriously.
hdr->ai_flags = htonl(ai->ai_flags);
hdr->ai_family = htonl(ai->ai_family);
hdr->ai_socktype = htonl(ai->ai_socktype);
hdr->ai_protocol = htonl(ai->ai_protocol);
hdr->ai_addrlen = ai->ai_addr == NULL ? 0 : htonl((u32)ai->ai_addrlen);
if(hdr->ai_addrlen == 0)
*(u32 *)((u8 *)hdr + sizeof(struct addrinfo_serialized_hdr)) = 0;
else {
// Nintendo just byteswaps everything recursively... even fields that are already byteswapped.
switch(ai->ai_family) {
case AF_INET: {
struct sockaddr_in sa = {0};
memcpy(&sa, ai->ai_addr, subsize1 <= sizeof(struct sockaddr_in) ? subsize1 : sizeof(struct sockaddr_in));
sa.sin_port = htons(sa.sin_port);
sa.sin_addr.s_addr = htonl(sa.sin_addr.s_addr);
memcpy((u8 *)hdr + sizeof(struct addrinfo_serialized_hdr), &sa, sizeof(struct sockaddr_in));
break;
}
case AF_INET6: {
struct sockaddr_in6 sa6 = {0};
memcpy(&sa6, ai->ai_addr, subsize1 <= sizeof(struct sockaddr_in6) ? subsize1 : sizeof(struct sockaddr_in6));
sa6.sin6_port = htons(sa6.sin6_port);
sa6.sin6_flowinfo = htonl(sa6.sin6_flowinfo);
sa6.sin6_scope_id = htonl(sa6.sin6_scope_id);
memcpy((u8 *)hdr + sizeof(struct addrinfo_serialized_hdr), &sa6, sizeof(struct sockaddr_in6));
break;
}
default:
memcpy((u8 *)hdr + sizeof(struct addrinfo_serialized_hdr), ai->ai_addr, subsize1);
}
}
if(ai->ai_canonname == NULL)
*((u8 *)hdr + sizeof(struct addrinfo_serialized_hdr) + subsize1) = 0;
else
memcpy((u8 *)hdr + sizeof(struct addrinfo_serialized_hdr) + subsize1, ai->ai_canonname, subsize2);
return sizeof(struct addrinfo_serialized_hdr) + subsize1 + subsize2;
}
static struct addrinfo_serialized_hdr *_resolverSerializeAddrInfoList(size_t *out_size, const struct addrinfo *ai) {
size_t total_addrlen = 0, total_namelen = 0, n = 0;
struct addrinfo_serialized_hdr *out, *pos;
for(const struct addrinfo *node = ai; node != NULL; node = node->ai_next) {
total_addrlen += node->ai_addrlen == 0 ? 4 : node->ai_addrlen;
total_namelen += node->ai_canonname == NULL ? 1 : (strlen(node->ai_canonname) + 1);
n++;
}
out = (struct addrinfo_serialized_hdr *)malloc(sizeof(struct addrinfo_serialized_hdr) * n + total_addrlen + total_namelen + 4);
if(out == NULL)
return NULL;
pos = out;
for(const struct addrinfo *node = ai; node != NULL; node = node->ai_next) {
size_t len = _resolverSerializeAddrInfo(pos, node);
pos = (struct addrinfo_serialized_hdr *)((u8 *)pos + len);
}
*(u32 *)pos = 0; // Sentinel value
*out_size = (u8 *)pos - (u8 *)out + 4;
return out;
}
static struct addrinfo *_resolverDeserializeAddrInfo(size_t *out_len, const struct addrinfo_serialized_hdr *hdr) {
struct addrinfo_node {
struct addrinfo info;
struct sockaddr_storage addr;
char canonname[];
};
size_t subsize1 = hdr->ai_addrlen == 0 ? 4 : ntohl(hdr->ai_addrlen);
size_t subsize2 = strlen((const char *)hdr + sizeof(struct addrinfo_serialized_hdr) + subsize1) + 1;
struct addrinfo_node *node = (struct addrinfo_node *)malloc(sizeof(struct addrinfo_node) + subsize2);
*out_len = sizeof(struct addrinfo_serialized_hdr) + subsize1 + subsize2;
if(node == NULL)
return NULL;
node->info.ai_flags = ntohl(hdr->ai_flags);
node->info.ai_family = ntohl(hdr->ai_family);
node->info.ai_socktype = ntohl(hdr->ai_socktype);
node->info.ai_protocol = ntohl(hdr->ai_protocol);
node->info.ai_addrlen = ntohl(hdr->ai_addrlen);
// getaddrinfo enforces addrlen = sizeof(struct sockaddr) and family = AF_INET, ie. only IPv4, anyways...
if(node->info.ai_addrlen > sizeof(struct sockaddr_storage))
node->info.ai_addrlen = sizeof(struct sockaddr_storage);
if(node->info.ai_addrlen == 0)
node->info.ai_addr = NULL;
else {
node->info.ai_addr = (struct sockaddr *)&node->addr;
memcpy(node->info.ai_addr, (const u8 *)hdr + sizeof(struct addrinfo_serialized_hdr), node->info.ai_addrlen);
// Nintendo just byteswaps everything recursively... even fields that are already byteswapped.
switch(node->info.ai_family) {
case AF_INET: {
struct sockaddr_in *sa = (struct sockaddr_in *)node->info.ai_addr;
sa->sin_len = 6;
sa->sin_port = ntohs(sa->sin_port);
sa->sin_addr.s_addr = ntohl(sa->sin_addr.s_addr);
break;
}
case AF_INET6: {
struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)node->info.ai_addr;
sa6->sin6_port = ntohs(sa6->sin6_port);
sa6->sin6_flowinfo = ntohl(sa6->sin6_flowinfo);
sa6->sin6_scope_id = ntohl(sa6->sin6_scope_id);
break;
}
default:
break;
}
}
if(subsize2 == 1)
node->info.ai_canonname = NULL;
else {
node->info.ai_canonname = node->canonname;
memcpy(node->info.ai_canonname, (const u8 *)hdr + sizeof(struct addrinfo_serialized_hdr) + subsize1, subsize2);
}
node->info.ai_next = NULL;
return &node->info;
}
static struct addrinfo *_resolverDeserializeAddrInfoList(struct addrinfo_serialized_hdr *hdr) {
struct addrinfo *first = NULL, *prev = NULL;
while(hdr->magic == htonl(0xBEEFCAFE)) {
size_t len;
struct addrinfo *node = _resolverDeserializeAddrInfo(&len, hdr);
if(node == NULL) {
if(first != NULL)
freeaddrinfo(first);
return NULL;
}
if(first == NULL)
first = node;
if(prev != NULL)
prev->ai_next = node;
prev = node;
hdr = (struct addrinfo_serialized_hdr *)((u8 *)hdr + len);
}
return first;
}
void freehostent(struct hostent *he) {
free(he);
}
void freeaddrinfo(struct addrinfo *ai) {
if(ai == NULL) return; // not specified by POSIX, but that's convenient (FreeBSD does this too, etc.).
for(struct addrinfo *node = ai, *next; node != NULL; node = next) {
next = node->ai_next;
free(node);
}
}
struct hostent *gethostbyname(const char *name) {
Result rc = 0;
void *out_he_serialized = malloc(g_resolverHostByNameBufferSize);
struct hostent *he = NULL;
u32 ret = 0;
u32 errno_ = 0;
if(out_he_serialized == NULL) {
h_errno = NO_RECOVERY;
errno = ENOMEM; // POSIX leaves this unspecified
goto cleanup;
}
rc = sfdnsresGetHostByNameRequest(
0,
true,
name,
&ret,
&errno_,
out_he_serialized, g_resolverHostByNameBufferSize,
NULL);
if(rc == 0xD401) {
h_errno = NO_RECOVERY;
errno = EFAULT; // POSIX leaves this unspecified
goto cleanup;
}
else if(R_FAILED(rc) && R_MODULE(rc) == 1) { // Kernel
h_errno = TRY_AGAIN;
errno = EAGAIN; // POSIX leaves this unspecified
goto cleanup;
}
else if(R_FAILED(rc)) {
h_errno = NO_RECOVERY;
errno = EINVAL; // POSIX leaves this unspecified
goto cleanup;
}
if(ret != NETDB_SUCCESS) {
h_errno = ret;
errno = errno_; // POSIX leaves this unspecified
goto cleanup;
}
he = _resolverDeserializeHostent(&h_errno, out_he_serialized);
if(he == NULL) {
h_errno = NO_RECOVERY;
errno = ENOMEM; // POSIX leaves this unspecified
}
cleanup:
g_resolverResult = rc;
free(out_he_serialized);
return he;
}
struct hostent *gethostbyaddr(const void *addr, socklen_t len, int type) {
Result rc = 0;
void *out_he_serialized = malloc(g_resolverHostByAddrBufferSize);
struct hostent *he = NULL;
u32 ret = 0;
u32 errno_ = 0;
if(out_he_serialized == NULL) {
h_errno = NO_RECOVERY;
errno = ENOMEM; // POSIX leaves this unspecified
goto cleanup;
}
rc = sfdnsresGetHostByAddrRequest(
addr, len,
type,
0,
&ret,
&errno_,
out_he_serialized, g_resolverHostByAddrBufferSize,
NULL);
if(rc == 0xD401) {
h_errno = NO_RECOVERY; // POSIX leaves this unspecified
errno = EFAULT;
goto cleanup;
}
else if(R_FAILED(rc) && R_MODULE(rc) == 1) { // Kernel
h_errno = TRY_AGAIN;
errno = EAGAIN; // POSIX leaves this unspecified
goto cleanup;
}
else if(R_FAILED(rc)) {
h_errno = NO_RECOVERY;
errno = EINVAL; // POSIX leaves this unspecified
goto cleanup;
}
if(ret != NETDB_SUCCESS) {
h_errno = ret;
errno = errno_; // POSIX leaves this unspecified
goto cleanup;
}
he = _resolverDeserializeHostent(&h_errno, out_he_serialized);
if(he == NULL) {
h_errno = NO_RECOVERY;
errno = ENOMEM; // POSIX leaves this unspecified
}
cleanup:
g_resolverResult = rc;
free(out_he_serialized);
return he;
}
const char *hstrerror(int err) {
static __thread char buf[0x80]; // ResolverOptionLocalKey::GetHostErrorStringBufferSizeUnsigned64
Result rc = sfdnsresGetHostStringErrorRequest(err, buf, sizeof(buf));
if(R_FAILED(rc)) // a bit limiting, given the broad range of errors the kernel can give to us...
strcpy(buf, "System busy, try again.");
g_resolverResult = rc;
return buf;
}
void herror(const char *str) {
fprintf(stderr, "%s: %s\n", str, hstrerror(h_errno));
}
const char *gai_strerror(int err) {
static __thread char buf[0x80]; // ResolverOptionLocalKey::GaiErrorStringBufferSizeUnsigned64
Result rc = sfdnsresGetGaiStringErrorRequest(err, buf, sizeof(buf));
if(R_FAILED(rc))
strcpy(buf, "System busy, try again.");
g_resolverResult = rc;
return buf;
}
int getaddrinfo(const char *node, const char *service, const struct addrinfo *hints, struct addrinfo **res) {
if (!node && !service)
return EAI_NONAME;
if (!res) {
errno = EINVAL;
return EAI_SYSTEM;
}
if (!g_resolverAddrInfoBufferSize) {
errno = ENOSPC;
return EAI_SYSTEM;
}
size_t hints_sz = 0;
struct addrinfo_serialized_hdr *hints_serialized = NULL;
if (hints) {
// TODO: fixed size for serialized hints (g_resolverAddrInfoHintsBufferSize)
(void)g_resolverAddrInfoHintsBufferSize;
hints_serialized = _resolverSerializeAddrInfoList(&hints_sz, hints);
if (!hints_serialized) {
errno = ENOMEM;
return EAI_MEMORY;
}
}
struct addrinfo_serialized_hdr *out_serialized = malloc(g_resolverAddrInfoBufferSize);
if (!out_serialized) {
free(hints_serialized);
errno = ENOMEM;
return EAI_FAIL;
}
s32 gaie = 0;
Result rc = sfdnsresGetAddrInfoRequest(
0,
true,
node,
service,
hints_serialized, hints_sz,
out_serialized, g_resolverAddrInfoBufferSize,
(u32*)&errno,
&gaie,
NULL);
g_resolverResult = rc;
free(hints_serialized);
if (R_FAILED(rc)) {
if (R_MODULE(rc) == 21) // SM
errno = EAGAIN;
else if (R_MODULE(rc) == 1) // Kernel
errno = EFAULT;
else
errno = EPIPE;
gaie = EAI_SYSTEM;
}
if (gaie == 0) {
*res = _resolverDeserializeAddrInfoList(out_serialized);
if (!*res) {
errno = ENOMEM;
gaie = EAI_MEMORY;
}
}
free(out_serialized);
return gaie;
}
int getnameinfo(const struct sockaddr *sa, socklen_t salen,
char *host, socklen_t hostlen,
char *serv, socklen_t servlen,
int flags) {
Result rc = 0;
u32 errno_ = 0;
s32 gaie = 0;
rc = sfdnsresGetNameInfoRequest(
flags,
sa, salen,
host, hostlen,
serv, servlen,
0,
&errno_,
&gaie);
if(rc == 0xD401) {
gaie = EAI_SYSTEM;
errno = EFAULT;
goto cleanup;
}
else if(R_FAILED(rc) && R_MODULE(rc) == 1) { // Kernel
gaie = EAI_AGAIN;
goto cleanup;
}
else if(R_FAILED(rc)) {
gaie = EAI_FAIL;
goto cleanup;
}
if(gaie != 0) {
if(gaie == EAI_SYSTEM)
errno = errno_;
}
cleanup:
g_resolverResult = rc;
return gaie;
}
long gethostid(void) {
u32 id = INADDR_LOOPBACK;
Result rc = nifmInitialize();
if (R_SUCCEEDED(rc)) {
rc = nifmGetCurrentIpAddress(&id);
nifmExit();
}
g_resolverResult = rc;
return id;
}
int gethostname(char *name, size_t namelen) {
// The Switch doesn't have a proper name, so let's use its IP
struct in_addr in;
in.s_addr = gethostid();
const char *hostname = inet_ntop(AF_INET, &in, name, namelen);
return hostname == NULL ? -1 : 0;
}
// Unimplementable functions, left for compliance:
struct hostent *gethostent(void) { h_errno = NO_RECOVERY; errno = ENOSYS; return NULL; }
struct netent *getnetbyaddr(uint32_t a, int b) { (void)a; (void)b; h_errno = NO_RECOVERY; errno = ENOSYS; return NULL; }
struct netent *getnetbyname(const char *s) { (void)s; h_errno = NO_RECOVERY; errno = ENOSYS; return NULL; }
struct netent *getnetent(void) { h_errno = NO_RECOVERY; errno = ENOSYS; return NULL; }
struct protoent *getprotobyname(const char *s) { (void)s; h_errno = NO_RECOVERY; errno = ENOSYS; return NULL; }
struct protoent *getprotobynumber(int a) { (void)a; h_errno = NO_RECOVERY; errno = ENOSYS; return NULL; }
struct protoent *getprotoent(void) { h_errno = NO_RECOVERY; errno = ENOSYS; return NULL; }
struct servent *getservbyname(const char *s1, const char *s2) { (void)s1; (void)s2; h_errno = NO_RECOVERY; errno = ENOSYS; return NULL; }
struct servent *getservbyport(int a, const char *s) { (void)a; (void)s; h_errno = NO_RECOVERY; errno = ENOSYS; return NULL; }
struct servent *getservent(void) { h_errno = NO_RECOVERY; errno = ENOSYS; return NULL; }
void sethostent(int a) { (void)a;}
void setnetent(int a) { (void)a;}
void setprotoent(int a) { (void)a; }