mirror of
https://github.com/Divested-Mobile/DivestOS-Build.git
synced 2024-08-23 10:45:25 +00:00
660 lines
18 KiB
Diff
660 lines
18 KiB
Diff
![]() |
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
|
||
|
From: Tom Marshall <tdm.code@gmail.com>
|
||
|
Date: Tue, 25 Aug 2020 08:31:32 -0700
|
||
|
Subject: [PATCH] DnsResolver: Sort and cache hosts file data for fast lookup
|
||
|
|
||
|
The hosts file is normally searched linearly. This is very slow when
|
||
|
the file is large. To mitigate this, read the hosts file and sort the
|
||
|
entries in an in-memory cache. When an address is requested via
|
||
|
gethostbyname or getaddrinfo, binary search the cache.
|
||
|
|
||
|
In case where the cache is not available, return a suitable error code
|
||
|
and fall back to the existing lookup code.
|
||
|
|
||
|
This has been written to behave as much like the existing lookup code as
|
||
|
possible. But note bionic and glibc differ in behavior for some corner
|
||
|
cases. Choose the most standard compliant behavior for these where
|
||
|
possible. Otherwise choose the behavior that seems most reasonable.
|
||
|
|
||
|
Note: this change is the analogue of the bionic change of the same name.
|
||
|
Both should be kept in sync.
|
||
|
|
||
|
Change-Id: I5926493864d4b1291ae83f8b601bf5dcc54085cd
|
||
|
---
|
||
|
Android.bp | 1 +
|
||
|
getaddrinfo.cpp | 9 +
|
||
|
hosts_cache.cpp | 523 ++++++++++++++++++++++++++++++++++++++++++++++++
|
||
|
hosts_cache.h | 28 +++
|
||
|
sethostent.cpp | 7 +
|
||
|
5 files changed, 568 insertions(+)
|
||
|
create mode 100644 hosts_cache.cpp
|
||
|
create mode 100644 hosts_cache.h
|
||
|
|
||
|
diff --git a/Android.bp b/Android.bp
|
||
|
index 696d721..86c9cf9 100644
|
||
|
--- a/Android.bp
|
||
|
+++ b/Android.bp
|
||
|
@@ -164,6 +164,7 @@ cc_library {
|
||
|
"getaddrinfo.cpp",
|
||
|
"gethnamaddr.cpp",
|
||
|
"sethostent.cpp",
|
||
|
+ "hosts_cache.cpp",
|
||
|
"res_cache.cpp",
|
||
|
"res_comp.cpp",
|
||
|
"res_debug.cpp",
|
||
|
diff --git a/getaddrinfo.cpp b/getaddrinfo.cpp
|
||
|
index 23e7e44..f0c0ba8 100644
|
||
|
--- a/getaddrinfo.cpp
|
||
|
+++ b/getaddrinfo.cpp
|
||
|
@@ -66,6 +66,8 @@
|
||
|
#include "resolv_private.h"
|
||
|
#include "util.h"
|
||
|
|
||
|
+#include "hosts_cache.h"
|
||
|
+
|
||
|
#define ANY 0
|
||
|
|
||
|
using android::net::NetworkDnsEventReported;
|
||
|
@@ -1557,6 +1559,13 @@ static bool files_getaddrinfo(const size_t netid, const char* name, const addrin
|
||
|
FILE* hostf = nullptr;
|
||
|
|
||
|
cur = &sentinel;
|
||
|
+
|
||
|
+ int hc_error = hc_getaddrinfo(name, pai, &cur);
|
||
|
+ if (hc_error != EAI_SYSTEM) {
|
||
|
+ *res = sentinel.ai_next;
|
||
|
+ return sentinel.ai_next != NULL;
|
||
|
+ }
|
||
|
+
|
||
|
_sethtent(&hostf);
|
||
|
while ((p = _gethtent(&hostf, name, pai)) != nullptr) {
|
||
|
cur->ai_next = p;
|
||
|
diff --git a/hosts_cache.cpp b/hosts_cache.cpp
|
||
|
new file mode 100644
|
||
|
index 0000000..a40fb40
|
||
|
--- /dev/null
|
||
|
+++ b/hosts_cache.cpp
|
||
|
@@ -0,0 +1,523 @@
|
||
|
+/*
|
||
|
+ * Copyright (C) 2016 The CyanogenMod Project
|
||
|
+ * Copyright (C) 2020 The LineageOS Project
|
||
|
+ *
|
||
|
+ * Licensed under the Apache License, Version 2.0 (the "License");
|
||
|
+ * you may not use this file except in compliance with the License.
|
||
|
+ * You may obtain a copy of the License at
|
||
|
+ *
|
||
|
+ * http://www.apache.org/licenses/LICENSE-2.0
|
||
|
+ *
|
||
|
+ * Unless required by applicable law or agreed to in writing, software
|
||
|
+ * distributed under the License is distributed on an "AS IS" BASIS,
|
||
|
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||
|
+ * See the License for the specific language governing permissions and
|
||
|
+ * limitations under the License.
|
||
|
+ */
|
||
|
+
|
||
|
+#include <fcntl.h>
|
||
|
+#include <netdb.h>
|
||
|
+#include <stdio.h>
|
||
|
+#include <stdlib.h>
|
||
|
+#include <string.h>
|
||
|
+#include <ctype.h>
|
||
|
+#include <strings.h>
|
||
|
+#include <sys/file.h>
|
||
|
+#include <sys/mman.h>
|
||
|
+#include <sys/socket.h>
|
||
|
+#include <sys/stat.h>
|
||
|
+#include <sys/types.h>
|
||
|
+#include <unistd.h>
|
||
|
+#include <utime.h>
|
||
|
+#include <pthread.h>
|
||
|
+
|
||
|
+#include <netinet/in6.h>
|
||
|
+#include <arpa/inet.h>
|
||
|
+#include <arpa/nameser.h>
|
||
|
+
|
||
|
+#include "hostent.h"
|
||
|
+#include "resolv_private.h"
|
||
|
+
|
||
|
+constexpr int MAXALIASES = 35;
|
||
|
+constexpr int MAXADDRS = 35;
|
||
|
+
|
||
|
+#define MAX_ADDRLEN (INET6_ADDRSTRLEN - (1 + 5))
|
||
|
+#define MAX_HOSTLEN MAXHOSTNAMELEN
|
||
|
+
|
||
|
+#define ESTIMATED_LINELEN 32
|
||
|
+#define HCFILE_ALLOC_SIZE 256
|
||
|
+
|
||
|
+/* From sethostent.c */
|
||
|
+#define ALIGNBYTES (sizeof(uintptr_t) - 1)
|
||
|
+#define ALIGN(p) (((uintptr_t)(p) + ALIGNBYTES) &~ ALIGNBYTES)
|
||
|
+
|
||
|
+/*
|
||
|
+ * Host cache entry for hcfile.c_data.
|
||
|
+ * Offsets are into hcfile.h_data.
|
||
|
+ * Strings are *not* terminated by NULL, but by whitespace (isspace) or '#'.
|
||
|
+ * Use hstr* functions with these.
|
||
|
+ */
|
||
|
+struct hcent
|
||
|
+{
|
||
|
+ uint32_t addr;
|
||
|
+ uint32_t name;
|
||
|
+};
|
||
|
+
|
||
|
+/*
|
||
|
+ * Overall host cache file state.
|
||
|
+ */
|
||
|
+struct hcfile
|
||
|
+{
|
||
|
+ int h_fd;
|
||
|
+ struct stat h_st;
|
||
|
+ char* h_data;
|
||
|
+
|
||
|
+ uint32_t c_alloc;
|
||
|
+ uint32_t c_len;
|
||
|
+ struct hcent* c_data;
|
||
|
+};
|
||
|
+static struct hcfile hcfile;
|
||
|
+static pthread_mutex_t hclock = PTHREAD_MUTEX_INITIALIZER;
|
||
|
+
|
||
|
+static size_t hstrlen(const char *s)
|
||
|
+{
|
||
|
+ const char *p = s;
|
||
|
+ while (*p && *p != '#' && !isspace(*p))
|
||
|
+ ++p;
|
||
|
+ return p - s;
|
||
|
+}
|
||
|
+
|
||
|
+static int hstrcmp(const char *a, const char *b)
|
||
|
+{
|
||
|
+ size_t alen = hstrlen(a);
|
||
|
+ size_t blen = hstrlen(b);
|
||
|
+ int res = strncmp(a, b, MIN(alen, blen));
|
||
|
+ if (res == 0)
|
||
|
+ res = alen - blen;
|
||
|
+ return res;
|
||
|
+}
|
||
|
+
|
||
|
+static char *hstrcpy(char *dest, const char *src)
|
||
|
+{
|
||
|
+ size_t len = hstrlen(src);
|
||
|
+ memcpy(dest, src, len);
|
||
|
+ dest[len] = '\0';
|
||
|
+ return dest;
|
||
|
+}
|
||
|
+
|
||
|
+static char *hstrdup(const char *s)
|
||
|
+{
|
||
|
+ size_t len = hstrlen(s);
|
||
|
+ char *dest = (char *)malloc(len + 1);
|
||
|
+ if (!dest)
|
||
|
+ return NULL;
|
||
|
+ memcpy(dest, s, len);
|
||
|
+ dest[len] = '\0';
|
||
|
+ return dest;
|
||
|
+}
|
||
|
+
|
||
|
+static int cmp_hcent_name(const void *a, const void *b)
|
||
|
+{
|
||
|
+ struct hcent *ea = (struct hcent *)a;
|
||
|
+ const char *na = hcfile.h_data + ea->name;
|
||
|
+ struct hcent *eb = (struct hcent *)b;
|
||
|
+ const char *nb = hcfile.h_data + eb->name;
|
||
|
+
|
||
|
+ return hstrcmp(na, nb);
|
||
|
+}
|
||
|
+
|
||
|
+static struct hcent *_hcfindname(const char *name)
|
||
|
+{
|
||
|
+ size_t first, last, mid;
|
||
|
+ struct hcent *cur = NULL;
|
||
|
+ int cmp;
|
||
|
+
|
||
|
+ if (hcfile.c_len == 0)
|
||
|
+ return NULL;
|
||
|
+
|
||
|
+ first = 0;
|
||
|
+ last = hcfile.c_len - 1;
|
||
|
+ mid = (first + last) / 2;
|
||
|
+ while (first <= last) {
|
||
|
+ cur = hcfile.c_data + mid;
|
||
|
+ cmp = hstrcmp(hcfile.h_data + cur->name, name);
|
||
|
+ if (cmp == 0)
|
||
|
+ goto found;
|
||
|
+ if (cmp < 0)
|
||
|
+ first = mid + 1;
|
||
|
+ else {
|
||
|
+ if (mid > 0)
|
||
|
+ last = mid - 1;
|
||
|
+ else
|
||
|
+ return NULL;
|
||
|
+ }
|
||
|
+ mid = (first + last) / 2;
|
||
|
+ }
|
||
|
+ return NULL;
|
||
|
+
|
||
|
+found:
|
||
|
+ while (cur > hcfile.c_data) {
|
||
|
+ struct hcent *prev = cur - 1;
|
||
|
+ cmp = cmp_hcent_name(cur, prev);
|
||
|
+ if (cmp)
|
||
|
+ break;
|
||
|
+ cur = prev;
|
||
|
+ }
|
||
|
+
|
||
|
+ return cur;
|
||
|
+}
|
||
|
+
|
||
|
+/*
|
||
|
+ * Find next name on line, if any.
|
||
|
+ *
|
||
|
+ * Assumes that line is terminated by LF.
|
||
|
+ */
|
||
|
+static const char *_hcnextname(const char *name)
|
||
|
+{
|
||
|
+ while (!isspace(*name)) {
|
||
|
+ if (*name == '#')
|
||
|
+ return NULL;
|
||
|
+ ++name;
|
||
|
+ }
|
||
|
+ while (isspace(*name)) {
|
||
|
+ if (*name == '\n')
|
||
|
+ return NULL;
|
||
|
+ ++name;
|
||
|
+ }
|
||
|
+ if (*name == '#')
|
||
|
+ return NULL;
|
||
|
+ return name;
|
||
|
+}
|
||
|
+
|
||
|
+static int _hcfilemmap(void)
|
||
|
+{
|
||
|
+ struct stat st;
|
||
|
+ int h_fd;
|
||
|
+ char *h_addr;
|
||
|
+ const char *p, *pend;
|
||
|
+ uint32_t c_alloc;
|
||
|
+
|
||
|
+ h_fd = open(_PATH_HOSTS, O_CLOEXEC);
|
||
|
+ if (h_fd < 0)
|
||
|
+ return -1;
|
||
|
+ if (flock(h_fd, LOCK_EX) != 0) {
|
||
|
+ close(h_fd);
|
||
|
+ return -1;
|
||
|
+ }
|
||
|
+
|
||
|
+ if (hcfile.h_data) {
|
||
|
+ memset(&st, 0, sizeof(st));
|
||
|
+ if (fstat(h_fd, &st) == 0) {
|
||
|
+ if (st.st_size == hcfile.h_st.st_size &&
|
||
|
+ st.st_mtime == hcfile.h_st.st_mtime) {
|
||
|
+ flock(h_fd, LOCK_UN);
|
||
|
+ close(h_fd);
|
||
|
+ return 0;
|
||
|
+ }
|
||
|
+ }
|
||
|
+ free(hcfile.c_data);
|
||
|
+ munmap(hcfile.h_data, hcfile.h_st.st_size);
|
||
|
+ close(hcfile.h_fd);
|
||
|
+ memset(&hcfile, 0, sizeof(struct hcfile));
|
||
|
+ }
|
||
|
+
|
||
|
+ if (fstat(h_fd, &st) != 0) {
|
||
|
+ flock(h_fd, LOCK_UN);
|
||
|
+ close(h_fd);
|
||
|
+ return -1;
|
||
|
+ }
|
||
|
+ h_addr = (char*)mmap(NULL, st.st_size, PROT_READ, MAP_SHARED, h_fd, 0);
|
||
|
+ if (h_addr == MAP_FAILED) {
|
||
|
+ flock(h_fd, LOCK_UN);
|
||
|
+ close(h_fd);
|
||
|
+ return -1;
|
||
|
+ }
|
||
|
+
|
||
|
+ hcfile.h_fd = h_fd;
|
||
|
+ hcfile.h_st = st;
|
||
|
+ hcfile.h_data = h_addr;
|
||
|
+
|
||
|
+ c_alloc = 0;
|
||
|
+ /*
|
||
|
+ * Do an initial allocation if the file is "large". Estimate
|
||
|
+ * 32 bytes per line and define "large" as more than half of
|
||
|
+ * the alloc growth size (256 entries).
|
||
|
+ */
|
||
|
+ if (st.st_size >= ESTIMATED_LINELEN * HCFILE_ALLOC_SIZE / 2) {
|
||
|
+ c_alloc = st.st_size / ESTIMATED_LINELEN;
|
||
|
+ hcfile.c_data = (struct hcent*)malloc(c_alloc * sizeof(struct hcent));
|
||
|
+ if (!hcfile.c_data) {
|
||
|
+ goto oom;
|
||
|
+ }
|
||
|
+ }
|
||
|
+
|
||
|
+ p = (const char *)h_addr;
|
||
|
+ pend = p + st.st_size;
|
||
|
+ while (p < pend) {
|
||
|
+ const char *eol, *addr, *name;
|
||
|
+ size_t len;
|
||
|
+ addr = p;
|
||
|
+ eol = (const char*)memchr(p, '\n', pend - p);
|
||
|
+ if (!eol)
|
||
|
+ break;
|
||
|
+ p = eol + 1;
|
||
|
+ if (*addr == '#' || *addr == '\n')
|
||
|
+ continue;
|
||
|
+ len = hstrlen(addr);
|
||
|
+ if (len > MAX_ADDRLEN)
|
||
|
+ continue;
|
||
|
+ name = addr + len;
|
||
|
+ while (name < eol && isspace(*name))
|
||
|
+ ++name;
|
||
|
+ while (name < eol) {
|
||
|
+ len = hstrlen(name);
|
||
|
+ if (len == 0)
|
||
|
+ break;
|
||
|
+ if (len < MAX_HOSTLEN) {
|
||
|
+ struct hcent *ent;
|
||
|
+ if (c_alloc <= hcfile.c_len) {
|
||
|
+ struct hcent *c_data;
|
||
|
+ c_alloc += HCFILE_ALLOC_SIZE;
|
||
|
+ c_data = (struct hcent*)realloc(hcfile.c_data, c_alloc * sizeof(struct hcent));
|
||
|
+ if (!c_data) {
|
||
|
+ goto oom;
|
||
|
+ }
|
||
|
+ hcfile.c_data = c_data;
|
||
|
+ }
|
||
|
+ ent = hcfile.c_data + hcfile.c_len;
|
||
|
+ ent->addr = addr - h_addr;
|
||
|
+ ent->name = name - h_addr;
|
||
|
+ ++hcfile.c_len;
|
||
|
+ }
|
||
|
+ name += len;
|
||
|
+ while (name < eol && isspace(*name))
|
||
|
+ ++name;
|
||
|
+ }
|
||
|
+ }
|
||
|
+
|
||
|
+ qsort(hcfile.c_data, hcfile.c_len,
|
||
|
+ sizeof(struct hcent), cmp_hcent_name);
|
||
|
+
|
||
|
+ flock(h_fd, LOCK_UN);
|
||
|
+
|
||
|
+ return 0;
|
||
|
+
|
||
|
+oom:
|
||
|
+ free(hcfile.c_data);
|
||
|
+ munmap(hcfile.h_data, hcfile.h_st.st_size);
|
||
|
+ flock(hcfile.h_fd, LOCK_UN);
|
||
|
+ close(hcfile.h_fd);
|
||
|
+ memset(&hcfile, 0, sizeof(struct hcfile));
|
||
|
+ return -1;
|
||
|
+}
|
||
|
+
|
||
|
+/*
|
||
|
+ * Caching version of getaddrinfo.
|
||
|
+ *
|
||
|
+ * If we find the requested host name in the cache, use getaddrinfo to
|
||
|
+ * populate the result for each address we find.
|
||
|
+ *
|
||
|
+ * Note glibc and bionic differ in the handling of ai_canonname. POSIX
|
||
|
+ * says that ai_canonname is only populated in the first result entry.
|
||
|
+ * glibc does this. bionic populates ai_canonname in all result entries.
|
||
|
+ * We choose the POSIX/glibc way here.
|
||
|
+ */
|
||
|
+int hc_getaddrinfo(const char *name, const struct addrinfo* hints, struct addrinfo** result)
|
||
|
+{
|
||
|
+ int ret = 0;
|
||
|
+ struct hcent *ent, *cur;
|
||
|
+ struct addrinfo *ai;
|
||
|
+ struct addrinfo rhints;
|
||
|
+ struct addrinfo *last;
|
||
|
+ int canonname = 0;
|
||
|
+ int cmp;
|
||
|
+
|
||
|
+ if (getenv("ANDROID_HOSTS_CACHE_DISABLE") != NULL)
|
||
|
+ return EAI_SYSTEM;
|
||
|
+
|
||
|
+ if (!name)
|
||
|
+ return EAI_SYSTEM;
|
||
|
+
|
||
|
+ pthread_mutex_lock(&hclock);
|
||
|
+
|
||
|
+ if (_hcfilemmap() != 0) {
|
||
|
+ ret = EAI_SYSTEM;
|
||
|
+ goto out;
|
||
|
+ }
|
||
|
+ ent = _hcfindname(name);
|
||
|
+ if (!ent) {
|
||
|
+ ret = EAI_NONAME;
|
||
|
+ goto out;
|
||
|
+ }
|
||
|
+
|
||
|
+ if (hints) {
|
||
|
+ canonname = (hints->ai_flags & AI_CANONNAME);
|
||
|
+ memcpy(&rhints, hints, sizeof(rhints));
|
||
|
+ rhints.ai_flags &= ~AI_CANONNAME;
|
||
|
+ }
|
||
|
+ else {
|
||
|
+ memset(&rhints, 0, sizeof(rhints));
|
||
|
+ }
|
||
|
+ rhints.ai_flags |= AI_NUMERICHOST;
|
||
|
+
|
||
|
+ last = NULL;
|
||
|
+ cur = ent;
|
||
|
+ do {
|
||
|
+ char addrstr[MAX_ADDRLEN];
|
||
|
+ struct addrinfo *res;
|
||
|
+
|
||
|
+ hstrcpy(addrstr, hcfile.h_data + cur->addr);
|
||
|
+
|
||
|
+ if (getaddrinfo_numeric(addrstr, nullptr, rhints, &res) == 0) {
|
||
|
+ if (!last)
|
||
|
+ (*result)->ai_next = res;
|
||
|
+ else
|
||
|
+ last->ai_next = res;
|
||
|
+ last = res;
|
||
|
+ while (last->ai_next)
|
||
|
+ last = last->ai_next;
|
||
|
+ }
|
||
|
+
|
||
|
+ if(cur + 1 >= hcfile.c_data + hcfile.c_len)
|
||
|
+ break;
|
||
|
+ cmp = cmp_hcent_name(cur, cur + 1);
|
||
|
+ cur = cur + 1;
|
||
|
+ }
|
||
|
+ while (!cmp);
|
||
|
+
|
||
|
+ if (last == NULL) {
|
||
|
+ /* This check is equivalent to (*result)->ai_next == NULL */
|
||
|
+ ret = EAI_NODATA;
|
||
|
+ goto out;
|
||
|
+ }
|
||
|
+
|
||
|
+ if (canonname) {
|
||
|
+ ai = (*result)->ai_next;
|
||
|
+ free(ai->ai_canonname);
|
||
|
+ ai->ai_canonname = hstrdup(hcfile.h_data + ent->name);
|
||
|
+ }
|
||
|
+
|
||
|
+out:
|
||
|
+ pthread_mutex_unlock(&hclock);
|
||
|
+ return ret;
|
||
|
+}
|
||
|
+
|
||
|
+/*
|
||
|
+ * Caching version of gethtbyname.
|
||
|
+ *
|
||
|
+ * Note glibc and bionic differ in the handling of aliases. glibc returns
|
||
|
+ * all aliases for all entries, regardless of whether they match h_addrtype.
|
||
|
+ * bionic returns only the aliases for the first hosts entry. We return all
|
||
|
+ * aliases for all IPv4 entries.
|
||
|
+ *
|
||
|
+ * Additionally, if an alias is IPv6 and the primary name for an alias also
|
||
|
+ * has an IPv4 entry, glibc will return the IPv4 address(es), but bionic
|
||
|
+ * will not. Neither do we.
|
||
|
+ */
|
||
|
+int hc_gethtbyname(const char *host, int af, struct getnamaddr *info)
|
||
|
+{
|
||
|
+ int ret = NETDB_SUCCESS;
|
||
|
+ struct hcent *ent, *cur;
|
||
|
+ int cmp;
|
||
|
+ size_t addrlen;
|
||
|
+ unsigned int naliases = 0;
|
||
|
+ char *aliases[MAXALIASES];
|
||
|
+ unsigned int naddrs = 0;
|
||
|
+ char *addr_ptrs[MAXADDRS];
|
||
|
+ unsigned int n;
|
||
|
+
|
||
|
+ if (getenv("ANDROID_HOSTS_CACHE_DISABLE") != NULL)
|
||
|
+ return NETDB_INTERNAL;
|
||
|
+
|
||
|
+ switch (af) {
|
||
|
+ case AF_INET: addrlen = NS_INADDRSZ; break;
|
||
|
+ case AF_INET6: addrlen = NS_IN6ADDRSZ; break;
|
||
|
+ default:
|
||
|
+ return NETDB_INTERNAL;
|
||
|
+ }
|
||
|
+
|
||
|
+ pthread_mutex_lock(&hclock);
|
||
|
+
|
||
|
+ if (_hcfilemmap() != 0) {
|
||
|
+ ret = NETDB_INTERNAL;
|
||
|
+ goto out;
|
||
|
+ }
|
||
|
+
|
||
|
+ ent = _hcfindname(host);
|
||
|
+ if (!ent) {
|
||
|
+ ret = HOST_NOT_FOUND;
|
||
|
+ goto out;
|
||
|
+ }
|
||
|
+
|
||
|
+ cur = ent;
|
||
|
+ do {
|
||
|
+ char addr[16];
|
||
|
+ char addrstr[MAX_ADDRLEN];
|
||
|
+ char namestr[MAX_HOSTLEN];
|
||
|
+ const char *name;
|
||
|
+
|
||
|
+ hstrcpy(addrstr, hcfile.h_data + cur->addr);
|
||
|
+ if (inet_pton(af, addrstr, &addr) == 1) {
|
||
|
+ char *aligned;
|
||
|
+ /* First match is considered the official hostname */
|
||
|
+ if (naddrs == 0) {
|
||
|
+ hstrcpy(namestr, hcfile.h_data + cur->name);
|
||
|
+ HENT_SCOPY(info->hp->h_name, namestr, info->buf, info->buflen);
|
||
|
+ }
|
||
|
+ for (name = hcfile.h_data + cur->name; name; name = _hcnextname(name)) {
|
||
|
+ if (!hstrcmp(name, host))
|
||
|
+ continue;
|
||
|
+ hstrcpy(namestr, name);
|
||
|
+ HENT_SCOPY(aliases[naliases], namestr, info->buf, info->buflen);
|
||
|
+ ++naliases;
|
||
|
+ if (naliases >= MAXALIASES)
|
||
|
+ goto nospc;
|
||
|
+ }
|
||
|
+ aligned = (char *)ALIGN(info->buf);
|
||
|
+ if (info->buf != aligned) {
|
||
|
+ if ((ptrdiff_t)info->buflen < (aligned - info->buf))
|
||
|
+ goto nospc;
|
||
|
+ info->buflen -= (aligned - info->buf);
|
||
|
+ info->buf = aligned;
|
||
|
+ }
|
||
|
+ HENT_COPY(addr_ptrs[naddrs], addr, addrlen, info->buf, info->buflen);
|
||
|
+ ++naddrs;
|
||
|
+ if (naddrs >= MAXADDRS)
|
||
|
+ goto nospc;
|
||
|
+ }
|
||
|
+
|
||
|
+ if(cur + 1 >= hcfile.c_data + hcfile.c_len)
|
||
|
+ break;
|
||
|
+ cmp = cmp_hcent_name(cur, cur + 1);
|
||
|
+ cur = cur + 1;
|
||
|
+ }
|
||
|
+ while (!cmp);
|
||
|
+
|
||
|
+ if (naddrs == 0) {
|
||
|
+ ret = HOST_NOT_FOUND;
|
||
|
+ goto out;
|
||
|
+ }
|
||
|
+
|
||
|
+ addr_ptrs[naddrs++] = NULL;
|
||
|
+ aliases[naliases++] = NULL;
|
||
|
+
|
||
|
+ /* hp->h_name already populated */
|
||
|
+ HENT_ARRAY(info->hp->h_aliases, naliases, info->buf, info->buflen);
|
||
|
+ for (n = 0; n < naliases; ++n) {
|
||
|
+ info->hp->h_aliases[n] = aliases[n];
|
||
|
+ }
|
||
|
+ info->hp->h_addrtype = af;
|
||
|
+ info->hp->h_length = addrlen;
|
||
|
+ HENT_ARRAY(info->hp->h_addr_list, naddrs, info->buf, info->buflen);
|
||
|
+ for (n = 0; n < naddrs; ++n) {
|
||
|
+ info->hp->h_addr_list[n] = addr_ptrs[n];
|
||
|
+ }
|
||
|
+
|
||
|
+out:
|
||
|
+ pthread_mutex_unlock(&hclock);
|
||
|
+ return ret;
|
||
|
+
|
||
|
+nospc:
|
||
|
+ ret = NETDB_INTERNAL;
|
||
|
+ goto out;
|
||
|
+}
|
||
|
diff --git a/hosts_cache.h b/hosts_cache.h
|
||
|
new file mode 100644
|
||
|
index 0000000..55138dc
|
||
|
--- /dev/null
|
||
|
+++ b/hosts_cache.h
|
||
|
@@ -0,0 +1,28 @@
|
||
|
+/*
|
||
|
+ * Copyright (C) 2016 The CyanogenMod Project
|
||
|
+ * Copyright (C) 2020 The LineageOS Project
|
||
|
+ *
|
||
|
+ * Licensed under the Apache License, Version 2.0 (the "License");
|
||
|
+ * you may not use this file except in compliance with the License.
|
||
|
+ * You may obtain a copy of the License at
|
||
|
+ *
|
||
|
+ * http://www.apache.org/licenses/LICENSE-2.0
|
||
|
+ *
|
||
|
+ * Unless required by applicable law or agreed to in writing, software
|
||
|
+ * distributed under the License is distributed on an "AS IS" BASIS,
|
||
|
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||
|
+ * See the License for the specific language governing permissions and
|
||
|
+ * limitations under the License.
|
||
|
+ */
|
||
|
+
|
||
|
+#ifndef NETD_RESOLV_HOSTS_CACHE_H
|
||
|
+#define NETD_RESOLV_HOSTS_CACHE_H
|
||
|
+
|
||
|
+struct getnamaddr;
|
||
|
+
|
||
|
+int hc_getaddrinfo(const char* name, const struct addrinfo* hints,
|
||
|
+ struct addrinfo** result);
|
||
|
+
|
||
|
+int hc_gethtbyname(const char *host, int af, struct getnamaddr *info);
|
||
|
+
|
||
|
+#endif
|
||
|
diff --git a/sethostent.cpp b/sethostent.cpp
|
||
|
index de94fce..64de4c3 100644
|
||
|
--- a/sethostent.cpp
|
||
|
+++ b/sethostent.cpp
|
||
|
@@ -43,6 +43,8 @@
|
||
|
#include "hostent.h"
|
||
|
#include "resolv_private.h"
|
||
|
|
||
|
+#include "hosts_cache.h"
|
||
|
+
|
||
|
constexpr int MAXALIASES = 35;
|
||
|
constexpr int MAXADDRS = 35;
|
||
|
|
||
|
@@ -72,6 +74,11 @@ int _hf_gethtbyname2(const char* name, int af, getnamaddr* info) {
|
||
|
char* aliases[MAXALIASES];
|
||
|
char* addr_ptrs[MAXADDRS];
|
||
|
|
||
|
+ int rc = hc_gethtbyname(name, af, info);
|
||
|
+ if (rc != NETDB_INTERNAL) {
|
||
|
+ return (rc == NETDB_SUCCESS ? 0 : EAI_NODATA);
|
||
|
+ }
|
||
|
+
|
||
|
FILE* hf = NULL;
|
||
|
sethostent_r(&hf);
|
||
|
if (hf == NULL) {
|