1238 lines
46 KiB
C++
1238 lines
46 KiB
C++
/*
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* Copyright (C) 2018 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#define LOG_TAG "LibBpfLoader"
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#include <errno.h>
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#include <linux/bpf.h>
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#include <linux/elf.h>
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#include <log/log.h>
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#include <stdint.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <sysexits.h>
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#include <sys/stat.h>
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#include <sys/utsname.h>
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#include <sys/wait.h>
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#include <unistd.h>
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// This is BpfLoader v0.19
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#define BPFLOADER_VERSION_MAJOR 0u
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#define BPFLOADER_VERSION_MINOR 19u
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#define BPFLOADER_VERSION ((BPFLOADER_VERSION_MAJOR << 16) | BPFLOADER_VERSION_MINOR)
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#include "bpf/BpfUtils.h"
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#include "bpf/bpf_map_def.h"
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#include "include/libbpf_android.h"
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#include <bpf/bpf.h>
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#include <cstdlib>
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#include <fstream>
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#include <iostream>
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#include <optional>
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#include <string>
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#include <unordered_map>
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#include <vector>
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#include <android-base/cmsg.h>
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#include <android-base/file.h>
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#include <android-base/strings.h>
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#include <android-base/unique_fd.h>
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#define BPF_FS_PATH "/sys/fs/bpf/"
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// Size of the BPF log buffer for verifier logging
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#define BPF_LOAD_LOG_SZ 0xfffff
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// Unspecified attach type is 0 which is BPF_CGROUP_INET_INGRESS.
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#define BPF_ATTACH_TYPE_UNSPEC BPF_CGROUP_INET_INGRESS
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using android::base::StartsWith;
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using android::base::unique_fd;
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using std::ifstream;
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using std::ios;
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using std::optional;
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using std::string;
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using std::vector;
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namespace android {
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namespace bpf {
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constexpr const char* lookupSelinuxContext(const domain d, const char* const unspecified = "") {
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switch (d) {
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case domain::unspecified: return unspecified;
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case domain::platform: return "fs_bpf";
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case domain::tethering: return "fs_bpf_tethering";
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case domain::net_private: return "fs_bpf_net_private";
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case domain::net_shared: return "fs_bpf_net_shared";
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case domain::netd_readonly: return "fs_bpf_netd_readonly";
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case domain::netd_shared: return "fs_bpf_netd_shared";
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case domain::vendor: return "fs_bpf_vendor";
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default: return "(unrecognized)";
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}
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}
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domain getDomainFromSelinuxContext(const char s[BPF_SELINUX_CONTEXT_CHAR_ARRAY_SIZE]) {
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for (domain d : AllDomains) {
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// Not sure how to enforce this at compile time, so abort() bpfloader at boot instead
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if (strlen(lookupSelinuxContext(d)) >= BPF_SELINUX_CONTEXT_CHAR_ARRAY_SIZE) abort();
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if (!strncmp(s, lookupSelinuxContext(d), BPF_SELINUX_CONTEXT_CHAR_ARRAY_SIZE)) return d;
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}
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ALOGW("ignoring unrecognized selinux_context '%32s'", s);
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// We should return 'unrecognized' here, however: returning unspecified will
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// result in the system simply using the default context, which in turn
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// will allow future expansion by adding more restrictive selinux types.
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// Older bpfloader will simply ignore that, and use the less restrictive default.
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// This does mean you CANNOT later add a *less* restrictive type than the default.
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//
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// Note: we cannot just abort() here as this might be a mainline module shipped optional update
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return domain::unspecified;
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}
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constexpr const char* lookupPinSubdir(const domain d, const char* const unspecified = "") {
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switch (d) {
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case domain::unspecified: return unspecified;
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case domain::platform: return "/";
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case domain::tethering: return "tethering/";
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case domain::net_private: return "net_private/";
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case domain::net_shared: return "net_shared/";
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case domain::netd_readonly: return "netd_readonly/";
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case domain::netd_shared: return "netd_shared/";
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case domain::vendor: return "vendor/";
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default: return "(unrecognized)";
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}
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};
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domain getDomainFromPinSubdir(const char s[BPF_PIN_SUBDIR_CHAR_ARRAY_SIZE]) {
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for (domain d : AllDomains) {
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// Not sure how to enforce this at compile time, so abort() bpfloader at boot instead
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if (strlen(lookupPinSubdir(d)) >= BPF_PIN_SUBDIR_CHAR_ARRAY_SIZE) abort();
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if (!strncmp(s, lookupPinSubdir(d), BPF_PIN_SUBDIR_CHAR_ARRAY_SIZE)) return d;
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}
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ALOGE("unrecognized pin_subdir '%32s'", s);
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// pin_subdir affects the object's full pathname,
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// and thus using the default would change the location and thus our code's ability to find it,
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// hence this seems worth treating as a true error condition.
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//
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// Note: we cannot just abort() here as this might be a mainline module shipped optional update
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// However, our callers will treat this as an error, and stop loading the specific .o,
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// which will fail bpfloader if the .o is marked critical.
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return domain::unrecognized;
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}
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static string pathToFilename(const string& path, bool noext = false) {
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vector<string> spath = android::base::Split(path, "/");
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string ret = spath.back();
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if (noext) {
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size_t lastindex = ret.find_last_of('.');
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return ret.substr(0, lastindex);
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}
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return ret;
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}
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typedef struct {
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const char* name;
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enum bpf_prog_type type;
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enum bpf_attach_type expected_attach_type;
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} sectionType;
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/*
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* Map section name prefixes to program types, the section name will be:
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* SECTION(<prefix>/<name-of-program>)
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* For example:
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* SECTION("tracepoint/sched_switch_func") where sched_switch_funcs
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* is the name of the program, and tracepoint is the type.
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*
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* However, be aware that you should not be directly using the SECTION() macro.
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* Instead use the DEFINE_(BPF|XDP)_(PROG|MAP)... & LICENSE/CRITICAL macros.
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*/
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sectionType sectionNameTypes[] = {
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{"bind4/", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, BPF_CGROUP_INET4_BIND},
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{"bind6/", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, BPF_CGROUP_INET6_BIND},
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{"cgroupskb/", BPF_PROG_TYPE_CGROUP_SKB, BPF_ATTACH_TYPE_UNSPEC},
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{"cgroupsock/", BPF_PROG_TYPE_CGROUP_SOCK, BPF_ATTACH_TYPE_UNSPEC},
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{"kprobe/", BPF_PROG_TYPE_KPROBE, BPF_ATTACH_TYPE_UNSPEC},
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{"perf_event/", BPF_PROG_TYPE_PERF_EVENT, BPF_ATTACH_TYPE_UNSPEC},
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{"schedact/", BPF_PROG_TYPE_SCHED_ACT, BPF_ATTACH_TYPE_UNSPEC},
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{"schedcls/", BPF_PROG_TYPE_SCHED_CLS, BPF_ATTACH_TYPE_UNSPEC},
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{"skfilter/", BPF_PROG_TYPE_SOCKET_FILTER, BPF_ATTACH_TYPE_UNSPEC},
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{"tracepoint/", BPF_PROG_TYPE_TRACEPOINT, BPF_ATTACH_TYPE_UNSPEC},
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{"xdp/", BPF_PROG_TYPE_XDP, BPF_ATTACH_TYPE_UNSPEC},
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};
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typedef struct {
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enum bpf_prog_type type;
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enum bpf_attach_type expected_attach_type;
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string name;
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vector<char> data;
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vector<char> rel_data;
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optional<struct bpf_prog_def> prog_def;
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unique_fd prog_fd; /* fd after loading */
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} codeSection;
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static int readElfHeader(ifstream& elfFile, Elf64_Ehdr* eh) {
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elfFile.seekg(0);
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if (elfFile.fail()) return -1;
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if (!elfFile.read((char*)eh, sizeof(*eh))) return -1;
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return 0;
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}
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/* Reads all section header tables into an Shdr array */
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static int readSectionHeadersAll(ifstream& elfFile, vector<Elf64_Shdr>& shTable) {
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Elf64_Ehdr eh;
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int ret = 0;
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ret = readElfHeader(elfFile, &eh);
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if (ret) return ret;
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elfFile.seekg(eh.e_shoff);
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if (elfFile.fail()) return -1;
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/* Read shdr table entries */
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shTable.resize(eh.e_shnum);
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if (!elfFile.read((char*)shTable.data(), (eh.e_shnum * eh.e_shentsize))) return -ENOMEM;
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return 0;
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}
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/* Read a section by its index - for ex to get sec hdr strtab blob */
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static int readSectionByIdx(ifstream& elfFile, int id, vector<char>& sec) {
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vector<Elf64_Shdr> shTable;
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int ret = readSectionHeadersAll(elfFile, shTable);
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if (ret) return ret;
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elfFile.seekg(shTable[id].sh_offset);
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if (elfFile.fail()) return -1;
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sec.resize(shTable[id].sh_size);
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if (!elfFile.read(sec.data(), shTable[id].sh_size)) return -1;
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return 0;
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}
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/* Read whole section header string table */
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static int readSectionHeaderStrtab(ifstream& elfFile, vector<char>& strtab) {
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Elf64_Ehdr eh;
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int ret = readElfHeader(elfFile, &eh);
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if (ret) return ret;
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ret = readSectionByIdx(elfFile, eh.e_shstrndx, strtab);
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if (ret) return ret;
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return 0;
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}
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/* Get name from offset in strtab */
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static int getSymName(ifstream& elfFile, int nameOff, string& name) {
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int ret;
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vector<char> secStrTab;
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ret = readSectionHeaderStrtab(elfFile, secStrTab);
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if (ret) return ret;
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if (nameOff >= (int)secStrTab.size()) return -1;
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name = string((char*)secStrTab.data() + nameOff);
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return 0;
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}
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/* Reads a full section by name - example to get the GPL license */
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static int readSectionByName(const char* name, ifstream& elfFile, vector<char>& data) {
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vector<char> secStrTab;
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vector<Elf64_Shdr> shTable;
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int ret;
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ret = readSectionHeadersAll(elfFile, shTable);
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if (ret) return ret;
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ret = readSectionHeaderStrtab(elfFile, secStrTab);
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if (ret) return ret;
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for (int i = 0; i < (int)shTable.size(); i++) {
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char* secname = secStrTab.data() + shTable[i].sh_name;
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if (!secname) continue;
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if (!strcmp(secname, name)) {
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vector<char> dataTmp;
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dataTmp.resize(shTable[i].sh_size);
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elfFile.seekg(shTable[i].sh_offset);
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if (elfFile.fail()) return -1;
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if (!elfFile.read((char*)dataTmp.data(), shTable[i].sh_size)) return -1;
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data = dataTmp;
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return 0;
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}
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}
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return -2;
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}
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unsigned int readSectionUint(const char* name, ifstream& elfFile, unsigned int defVal) {
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vector<char> theBytes;
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int ret = readSectionByName(name, elfFile, theBytes);
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if (ret) {
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ALOGD("Couldn't find section %s (defaulting to %u [0x%x]).", name, defVal, defVal);
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return defVal;
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} else if (theBytes.size() < sizeof(unsigned int)) {
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ALOGE("Section %s too short (defaulting to %u [0x%x]).", name, defVal, defVal);
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return defVal;
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} else {
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// decode first 4 bytes as LE32 uint, there will likely be more bytes due to alignment.
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unsigned int value = static_cast<unsigned char>(theBytes[3]);
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value <<= 8;
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value += static_cast<unsigned char>(theBytes[2]);
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value <<= 8;
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value += static_cast<unsigned char>(theBytes[1]);
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value <<= 8;
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value += static_cast<unsigned char>(theBytes[0]);
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ALOGI("Section %s value is %u [0x%x]", name, value, value);
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return value;
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}
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}
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static int readSectionByType(ifstream& elfFile, int type, vector<char>& data) {
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int ret;
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vector<Elf64_Shdr> shTable;
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ret = readSectionHeadersAll(elfFile, shTable);
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if (ret) return ret;
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for (int i = 0; i < (int)shTable.size(); i++) {
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if ((int)shTable[i].sh_type != type) continue;
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vector<char> dataTmp;
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dataTmp.resize(shTable[i].sh_size);
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elfFile.seekg(shTable[i].sh_offset);
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if (elfFile.fail()) return -1;
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if (!elfFile.read((char*)dataTmp.data(), shTable[i].sh_size)) return -1;
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data = dataTmp;
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return 0;
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}
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return -2;
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}
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static bool symCompare(Elf64_Sym a, Elf64_Sym b) {
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return (a.st_value < b.st_value);
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}
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static int readSymTab(ifstream& elfFile, int sort, vector<Elf64_Sym>& data) {
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int ret, numElems;
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Elf64_Sym* buf;
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vector<char> secData;
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ret = readSectionByType(elfFile, SHT_SYMTAB, secData);
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if (ret) return ret;
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buf = (Elf64_Sym*)secData.data();
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numElems = (secData.size() / sizeof(Elf64_Sym));
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data.assign(buf, buf + numElems);
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if (sort) std::sort(data.begin(), data.end(), symCompare);
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return 0;
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}
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static enum bpf_prog_type getSectionType(string& name) {
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for (auto& snt : sectionNameTypes)
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if (StartsWith(name, snt.name)) return snt.type;
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// TODO Remove this code when fuse-bpf is upstream and this BPF_PROG_TYPE_FUSE is fixed
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if (StartsWith(name, "fuse/")) {
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int result = BPF_PROG_TYPE_UNSPEC;
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ifstream("/sys/fs/fuse/bpf_prog_type_fuse") >> result;
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return static_cast<bpf_prog_type>(result);
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}
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return BPF_PROG_TYPE_UNSPEC;
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}
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static enum bpf_attach_type getExpectedAttachType(string& name) {
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for (auto& snt : sectionNameTypes)
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if (StartsWith(name, snt.name)) return snt.expected_attach_type;
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return BPF_ATTACH_TYPE_UNSPEC;
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}
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static string getSectionName(enum bpf_prog_type type)
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{
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for (auto& snt : sectionNameTypes)
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if (snt.type == type)
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return string(snt.name);
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return "UNKNOWN SECTION NAME " + std::to_string(type);
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}
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static int readProgDefs(ifstream& elfFile, vector<struct bpf_prog_def>& pd,
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size_t sizeOfBpfProgDef) {
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vector<char> pdData;
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int ret = readSectionByName("progs", elfFile, pdData);
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// Older file formats do not require a 'progs' section at all.
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// (We should probably figure out whether this is behaviour which is safe to remove now.)
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if (ret == -2) return 0;
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if (ret) return ret;
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if (pdData.size() % sizeOfBpfProgDef) {
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ALOGE("readProgDefs failed due to improper sized progs section, %zu %% %zu != 0",
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pdData.size(), sizeOfBpfProgDef);
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return -1;
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};
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int progCount = pdData.size() / sizeOfBpfProgDef;
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pd.resize(progCount);
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size_t trimmedSize = std::min(sizeOfBpfProgDef, sizeof(struct bpf_prog_def));
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const char* dataPtr = pdData.data();
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for (auto& p : pd) {
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// First we zero initialize
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memset(&p, 0, sizeof(p));
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// Then we set non-zero defaults
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p.bpfloader_max_ver = DEFAULT_BPFLOADER_MAX_VER; // v1.0
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// Then we copy over the structure prefix from the ELF file.
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memcpy(&p, dataPtr, trimmedSize);
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// Move to next struct in the ELF file
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dataPtr += sizeOfBpfProgDef;
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}
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return 0;
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}
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static int getSectionSymNames(ifstream& elfFile, const string& sectionName, vector<string>& names,
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optional<unsigned> symbolType = std::nullopt) {
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int ret;
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string name;
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vector<Elf64_Sym> symtab;
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vector<Elf64_Shdr> shTable;
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ret = readSymTab(elfFile, 1 /* sort */, symtab);
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if (ret) return ret;
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/* Get index of section */
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ret = readSectionHeadersAll(elfFile, shTable);
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if (ret) return ret;
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int sec_idx = -1;
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for (int i = 0; i < (int)shTable.size(); i++) {
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ret = getSymName(elfFile, shTable[i].sh_name, name);
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if (ret) return ret;
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if (!name.compare(sectionName)) {
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sec_idx = i;
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break;
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}
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}
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/* No section found with matching name*/
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if (sec_idx == -1) {
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ALOGW("No %s section could be found in elf object", sectionName.c_str());
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return -1;
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}
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for (int i = 0; i < (int)symtab.size(); i++) {
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if (symbolType.has_value() && ELF_ST_TYPE(symtab[i].st_info) != symbolType) continue;
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if (symtab[i].st_shndx == sec_idx) {
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string s;
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ret = getSymName(elfFile, symtab[i].st_name, s);
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if (ret) return ret;
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names.push_back(s);
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}
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}
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return 0;
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}
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static bool IsAllowed(bpf_prog_type type, const bpf_prog_type* allowed, size_t numAllowed) {
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if (allowed == nullptr) return true;
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for (size_t i = 0; i < numAllowed; i++) {
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if (type == allowed[i]) return true;
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}
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return false;
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}
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|
|
|
/* Read a section by its index - for ex to get sec hdr strtab blob */
|
|
static int readCodeSections(ifstream& elfFile, vector<codeSection>& cs, size_t sizeOfBpfProgDef,
|
|
const bpf_prog_type* allowed, size_t numAllowed) {
|
|
vector<Elf64_Shdr> shTable;
|
|
int entries, ret = 0;
|
|
|
|
ret = readSectionHeadersAll(elfFile, shTable);
|
|
if (ret) return ret;
|
|
entries = shTable.size();
|
|
|
|
vector<struct bpf_prog_def> pd;
|
|
ret = readProgDefs(elfFile, pd, sizeOfBpfProgDef);
|
|
if (ret) return ret;
|
|
vector<string> progDefNames;
|
|
ret = getSectionSymNames(elfFile, "progs", progDefNames);
|
|
if (!pd.empty() && ret) return ret;
|
|
|
|
for (int i = 0; i < entries; i++) {
|
|
string name;
|
|
codeSection cs_temp;
|
|
cs_temp.type = BPF_PROG_TYPE_UNSPEC;
|
|
|
|
ret = getSymName(elfFile, shTable[i].sh_name, name);
|
|
if (ret) return ret;
|
|
|
|
enum bpf_prog_type ptype = getSectionType(name);
|
|
|
|
if (ptype == BPF_PROG_TYPE_UNSPEC) continue;
|
|
|
|
if (!IsAllowed(ptype, allowed, numAllowed)) {
|
|
ALOGE("Program type %s not permitted here", getSectionName(ptype).c_str());
|
|
return -1;
|
|
}
|
|
|
|
// This must be done before '/' is replaced with '_'.
|
|
cs_temp.expected_attach_type = getExpectedAttachType(name);
|
|
|
|
string oldName = name;
|
|
|
|
// convert all slashes to underscores
|
|
std::replace(name.begin(), name.end(), '/', '_');
|
|
|
|
cs_temp.type = ptype;
|
|
cs_temp.name = name;
|
|
|
|
ret = readSectionByIdx(elfFile, i, cs_temp.data);
|
|
if (ret) return ret;
|
|
ALOGD("Loaded code section %d (%s)", i, name.c_str());
|
|
|
|
vector<string> csSymNames;
|
|
ret = getSectionSymNames(elfFile, oldName, csSymNames, STT_FUNC);
|
|
if (ret || !csSymNames.size()) return ret;
|
|
for (size_t i = 0; i < progDefNames.size(); ++i) {
|
|
if (!progDefNames[i].compare(csSymNames[0] + "_def")) {
|
|
cs_temp.prog_def = pd[i];
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Check for rel section */
|
|
if (cs_temp.data.size() > 0 && i < entries) {
|
|
ret = getSymName(elfFile, shTable[i + 1].sh_name, name);
|
|
if (ret) return ret;
|
|
|
|
if (name == (".rel" + oldName)) {
|
|
ret = readSectionByIdx(elfFile, i + 1, cs_temp.rel_data);
|
|
if (ret) return ret;
|
|
ALOGD("Loaded relo section %d (%s)", i, name.c_str());
|
|
}
|
|
}
|
|
|
|
if (cs_temp.data.size() > 0) {
|
|
cs.push_back(std::move(cs_temp));
|
|
ALOGD("Adding section %d to cs list", i);
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int getSymNameByIdx(ifstream& elfFile, int index, string& name) {
|
|
vector<Elf64_Sym> symtab;
|
|
int ret = 0;
|
|
|
|
ret = readSymTab(elfFile, 0 /* !sort */, symtab);
|
|
if (ret) return ret;
|
|
|
|
if (index >= (int)symtab.size()) return -1;
|
|
|
|
return getSymName(elfFile, symtab[index].st_name, name);
|
|
}
|
|
|
|
static bool waitpidTimeout(pid_t pid, int timeoutMs) {
|
|
// Add SIGCHLD to the signal set.
|
|
sigset_t child_mask, original_mask;
|
|
sigemptyset(&child_mask);
|
|
sigaddset(&child_mask, SIGCHLD);
|
|
if (sigprocmask(SIG_BLOCK, &child_mask, &original_mask) == -1) return false;
|
|
|
|
// Wait for a SIGCHLD notification.
|
|
errno = 0;
|
|
timespec ts = {0, timeoutMs * 1000000};
|
|
int wait_result = TEMP_FAILURE_RETRY(sigtimedwait(&child_mask, nullptr, &ts));
|
|
|
|
// Restore the original signal set.
|
|
sigprocmask(SIG_SETMASK, &original_mask, nullptr);
|
|
|
|
if (wait_result == -1) return false;
|
|
|
|
int status;
|
|
return TEMP_FAILURE_RETRY(waitpid(pid, &status, WNOHANG)) == pid;
|
|
}
|
|
|
|
static std::optional<unique_fd> getMapBtfInfo(const char* elfPath,
|
|
std::unordered_map<string, std::pair<uint32_t, uint32_t>> &btfTypeIds) {
|
|
unique_fd bpfloaderSocket, btfloaderSocket;
|
|
if (!android::base::Socketpair(AF_UNIX, SOCK_DGRAM | SOCK_NONBLOCK, 0, &bpfloaderSocket,
|
|
&btfloaderSocket)) {
|
|
return {};
|
|
}
|
|
|
|
unique_fd pipeRead, pipeWrite;
|
|
if (!android::base::Pipe(&pipeRead, &pipeWrite, O_NONBLOCK)) {
|
|
return {};
|
|
}
|
|
|
|
pid_t pid = fork();
|
|
if (pid < 0) return {};
|
|
if (!pid) {
|
|
bpfloaderSocket.reset();
|
|
pipeRead.reset();
|
|
auto socketFdStr = std::to_string(btfloaderSocket.release());
|
|
auto pipeFdStr = std::to_string(pipeWrite.release());
|
|
|
|
if (execl("/system/bin/btfloader", "/system/bin/btfloader", socketFdStr.c_str(),
|
|
pipeFdStr.c_str(), elfPath, NULL) == -1) {
|
|
ALOGW("exec btfloader failed with errno %d (%s)", errno, strerror(errno));
|
|
exit(EX_UNAVAILABLE);
|
|
}
|
|
}
|
|
btfloaderSocket.reset();
|
|
pipeWrite.reset();
|
|
if (!waitpidTimeout(pid, 100)) {
|
|
kill(pid, SIGKILL);
|
|
return {};
|
|
}
|
|
|
|
unique_fd btfFd;
|
|
if (android::base::ReceiveFileDescriptors(bpfloaderSocket, nullptr, 0, &btfFd)) return {};
|
|
|
|
std::string btfTypeIdStr;
|
|
if (!android::base::ReadFdToString(pipeRead, &btfTypeIdStr)) return {};
|
|
if (!btfFd.ok()) return {};
|
|
|
|
const auto mapTypeIdLines = android::base::Split(btfTypeIdStr, "\n");
|
|
for (const auto &line : mapTypeIdLines) {
|
|
const auto vec = android::base::Split(line, " ");
|
|
// Splitting on newline will give us one empty line
|
|
if (vec.size() != 3) continue;
|
|
const int kTid = atoi(vec[1].c_str());
|
|
const int vTid = atoi(vec[2].c_str());
|
|
if (!kTid || !vTid) return {};
|
|
btfTypeIds[vec[0]] = std::make_pair(kTid, vTid);
|
|
}
|
|
return btfFd;
|
|
}
|
|
|
|
static bool mapMatchesExpectations(unique_fd& fd, string& mapName, struct bpf_map_def& mapDef,
|
|
enum bpf_map_type type) {
|
|
// bpfGetFd... family of functions require at minimum a 4.14 kernel,
|
|
// so on 4.9 kernels just pretend the map matches our expectations.
|
|
// This isn't really a problem as we only really support 4.14+ anyway...
|
|
// Additionally we'll get almost equivalent test coverage on newer devices/kernels.
|
|
// This is because the primary failure mode we're trying to detect here
|
|
// is either a source code misconfiguration (which is likely kernel independent)
|
|
// or a newly introduced kernel feature/bug (which is unlikely to get backported to 4.9).
|
|
if (!isAtLeastKernelVersion(4, 14, 0)) return true;
|
|
|
|
// These asserts should *never* trigger, if one of them somehow does,
|
|
// it probably means a bpf .o file has been changed/replaced at runtime
|
|
// and bpfloader was manually rerun (normally it should only run *once*
|
|
// early during the boot process).
|
|
// Another possibility is that something is misconfigured in the code:
|
|
// most likely a shared map is declared twice differently.
|
|
// But such a change should never be checked into the source tree...
|
|
int fd_type = bpfGetFdMapType(fd);
|
|
int fd_key_size = bpfGetFdKeySize(fd);
|
|
int fd_value_size = bpfGetFdValueSize(fd);
|
|
int fd_max_entries = bpfGetFdMaxEntries(fd);
|
|
int fd_map_flags = bpfGetFdMapFlags(fd);
|
|
|
|
// DEVMAPs are readonly from the bpf program side's point of view, as such
|
|
// the kernel in kernel/bpf/devmap.c dev_map_init_map() will set the flag
|
|
int desired_map_flags = (int)mapDef.map_flags;
|
|
if (type == BPF_MAP_TYPE_DEVMAP || type == BPF_MAP_TYPE_DEVMAP_HASH)
|
|
desired_map_flags |= BPF_F_RDONLY_PROG;
|
|
|
|
// If anything doesn't match, just close the fd - it's of no use anyway.
|
|
if (fd_type != type) fd.reset();
|
|
if (fd_key_size != (int)mapDef.key_size) fd.reset();
|
|
if (fd_value_size != (int)mapDef.value_size) fd.reset();
|
|
if (fd_max_entries != (int)mapDef.max_entries) fd.reset();
|
|
if (fd_map_flags != desired_map_flags) fd.reset();
|
|
|
|
if (fd.ok()) return true;
|
|
|
|
ALOGE("bpf map name %s mismatch: desired/found: "
|
|
"type:%d/%d key:%u/%d value:%u/%d entries:%u/%d flags:%u/%d",
|
|
mapName.c_str(), type, fd_type, mapDef.key_size, fd_key_size, mapDef.value_size,
|
|
fd_value_size, mapDef.max_entries, fd_max_entries, desired_map_flags, fd_map_flags);
|
|
return false;
|
|
}
|
|
|
|
static int createMaps(const char* elfPath, ifstream& elfFile, vector<unique_fd>& mapFds,
|
|
const char* prefix, const unsigned long long allowedDomainBitmask,
|
|
const size_t sizeOfBpfMapDef) {
|
|
int ret;
|
|
vector<char> mdData, btfData;
|
|
vector<struct bpf_map_def> md;
|
|
vector<string> mapNames;
|
|
std::unordered_map<string, std::pair<uint32_t, uint32_t>> btfTypeIdMap;
|
|
string fname = pathToFilename(string(elfPath), true);
|
|
|
|
ret = readSectionByName("maps", elfFile, mdData);
|
|
if (ret == -2) return 0; // no maps to read
|
|
if (ret) return ret;
|
|
|
|
if (mdData.size() % sizeOfBpfMapDef) {
|
|
ALOGE("createMaps failed due to improper sized maps section, %zu %% %zu != 0",
|
|
mdData.size(), sizeOfBpfMapDef);
|
|
return -1;
|
|
};
|
|
|
|
int mapCount = mdData.size() / sizeOfBpfMapDef;
|
|
md.resize(mapCount);
|
|
size_t trimmedSize = std::min(sizeOfBpfMapDef, sizeof(struct bpf_map_def));
|
|
|
|
const char* dataPtr = mdData.data();
|
|
for (auto& m : md) {
|
|
// First we zero initialize
|
|
memset(&m, 0, sizeof(m));
|
|
// Then we set non-zero defaults
|
|
m.bpfloader_max_ver = DEFAULT_BPFLOADER_MAX_VER; // v1.0
|
|
m.max_kver = 0xFFFFFFFFu; // matches KVER_INF from bpf_helpers.h
|
|
// Then we copy over the structure prefix from the ELF file.
|
|
memcpy(&m, dataPtr, trimmedSize);
|
|
// Move to next struct in the ELF file
|
|
dataPtr += sizeOfBpfMapDef;
|
|
}
|
|
|
|
ret = getSectionSymNames(elfFile, "maps", mapNames);
|
|
if (ret) return ret;
|
|
|
|
unsigned btfMinBpfLoaderVer = readSectionUint("btf_min_bpfloader_ver", elfFile, 0);
|
|
unsigned btfMinKernelVer = readSectionUint("btf_min_kernel_ver", elfFile, 0);
|
|
unsigned kvers = kernelVersion();
|
|
|
|
std::optional<unique_fd> btfFd;
|
|
if ((BPFLOADER_VERSION >= btfMinBpfLoaderVer) && (kvers >= btfMinKernelVer) &&
|
|
(!readSectionByName(".BTF", elfFile, btfData))) {
|
|
btfFd = getMapBtfInfo(elfPath, btfTypeIdMap);
|
|
}
|
|
|
|
for (int i = 0; i < (int)mapNames.size(); i++) {
|
|
if (BPFLOADER_VERSION < md[i].bpfloader_min_ver) {
|
|
ALOGI("skipping map %s which requires bpfloader min ver 0x%05x", mapNames[i].c_str(),
|
|
md[i].bpfloader_min_ver);
|
|
mapFds.push_back(unique_fd());
|
|
continue;
|
|
}
|
|
|
|
if (BPFLOADER_VERSION >= md[i].bpfloader_max_ver) {
|
|
ALOGI("skipping map %s which requires bpfloader max ver 0x%05x", mapNames[i].c_str(),
|
|
md[i].bpfloader_max_ver);
|
|
mapFds.push_back(unique_fd());
|
|
continue;
|
|
}
|
|
|
|
if (kvers < md[i].min_kver) {
|
|
ALOGI("skipping map %s which requires kernel version 0x%x >= 0x%x",
|
|
mapNames[i].c_str(), kvers, md[i].min_kver);
|
|
mapFds.push_back(unique_fd());
|
|
continue;
|
|
}
|
|
|
|
if (kvers >= md[i].max_kver) {
|
|
ALOGI("skipping map %s which requires kernel version 0x%x < 0x%x",
|
|
mapNames[i].c_str(), kvers, md[i].max_kver);
|
|
mapFds.push_back(unique_fd());
|
|
continue;
|
|
}
|
|
|
|
enum bpf_map_type type = md[i].type;
|
|
if (type == BPF_MAP_TYPE_DEVMAP && !isAtLeastKernelVersion(4, 14, 0)) {
|
|
// On Linux Kernels older than 4.14 this map type doesn't exist, but it can kind
|
|
// of be approximated: ARRAY has the same userspace api, though it is not usable
|
|
// by the same ebpf programs. However, that's okay because the bpf_redirect_map()
|
|
// helper doesn't exist on 4.9 anyway (so the bpf program would fail to load,
|
|
// and thus needs to be tagged as 4.14+ either way), so there's nothing useful you
|
|
// could do with a DEVMAP anyway (that isn't already provided by an ARRAY)...
|
|
// Hence using an ARRAY instead of a DEVMAP simply makes life easier for userspace.
|
|
type = BPF_MAP_TYPE_ARRAY;
|
|
}
|
|
if (type == BPF_MAP_TYPE_DEVMAP_HASH && !isAtLeastKernelVersion(5, 4, 0)) {
|
|
// On Linux Kernels older than 5.4 this map type doesn't exist, but it can kind
|
|
// of be approximated: HASH has the same userspace visible api.
|
|
// However it cannot be used by ebpf programs in the same way.
|
|
// Since bpf_redirect_map() only requires 4.14, a program using a DEVMAP_HASH map
|
|
// would fail to load (due to trying to redirect to a HASH instead of DEVMAP_HASH).
|
|
// One must thus tag any BPF_MAP_TYPE_DEVMAP_HASH + bpf_redirect_map() using
|
|
// programs as being 5.4+...
|
|
type = BPF_MAP_TYPE_HASH;
|
|
}
|
|
|
|
domain selinux_context = getDomainFromSelinuxContext(md[i].selinux_context);
|
|
if (specified(selinux_context)) {
|
|
if (!inDomainBitmask(selinux_context, allowedDomainBitmask)) {
|
|
ALOGE("map %s has invalid selinux_context of %d (allowed bitmask 0x%llx)",
|
|
mapNames[i].c_str(), selinux_context, allowedDomainBitmask);
|
|
return -EINVAL;
|
|
}
|
|
ALOGI("map %s selinux_context [%32s] -> %d -> '%s' (%s)", mapNames[i].c_str(),
|
|
md[i].selinux_context, selinux_context, lookupSelinuxContext(selinux_context),
|
|
lookupPinSubdir(selinux_context));
|
|
}
|
|
|
|
domain pin_subdir = getDomainFromPinSubdir(md[i].pin_subdir);
|
|
if (unrecognized(pin_subdir)) return -ENOTDIR;
|
|
if (specified(pin_subdir)) {
|
|
if (!inDomainBitmask(pin_subdir, allowedDomainBitmask)) {
|
|
ALOGE("map %s has invalid pin_subdir of %d (allowed bitmask 0x%llx)",
|
|
mapNames[i].c_str(), pin_subdir, allowedDomainBitmask);
|
|
return -EINVAL;
|
|
}
|
|
ALOGI("map %s pin_subdir [%32s] -> %d -> '%s'", mapNames[i].c_str(), md[i].pin_subdir,
|
|
pin_subdir, lookupPinSubdir(pin_subdir));
|
|
}
|
|
|
|
// Format of pin location is /sys/fs/bpf/<pin_subdir|prefix>map_<filename>_<mapname>
|
|
// except that maps shared across .o's have empty <filename>
|
|
// Note: <filename> refers to the extension-less basename of the .o file.
|
|
string mapPinLoc = string(BPF_FS_PATH) + lookupPinSubdir(pin_subdir, prefix) + "map_" +
|
|
(md[i].shared ? "" : fname) + "_" + mapNames[i];
|
|
bool reuse = false;
|
|
unique_fd fd;
|
|
int saved_errno;
|
|
|
|
if (access(mapPinLoc.c_str(), F_OK) == 0) {
|
|
fd.reset(bpf_obj_get(mapPinLoc.c_str()));
|
|
saved_errno = errno;
|
|
ALOGD("bpf_create_map reusing map %s, ret: %d", mapNames[i].c_str(), fd.get());
|
|
reuse = true;
|
|
} else {
|
|
struct bpf_create_map_attr attr = {
|
|
.name = mapNames[i].c_str(),
|
|
.map_type = type,
|
|
.map_flags = md[i].map_flags,
|
|
.key_size = md[i].key_size,
|
|
.value_size = md[i].value_size,
|
|
.max_entries = md[i].max_entries,
|
|
};
|
|
if (btfFd.has_value() && btfTypeIdMap.find(mapNames[i]) != btfTypeIdMap.end()) {
|
|
attr.btf_fd = btfFd->get();
|
|
attr.btf_key_type_id = btfTypeIdMap.at(mapNames[i]).first;
|
|
attr.btf_value_type_id = btfTypeIdMap.at(mapNames[i]).second;
|
|
}
|
|
fd.reset(bcc_create_map_xattr(&attr, true));
|
|
saved_errno = errno;
|
|
ALOGD("bpf_create_map name %s, ret: %d", mapNames[i].c_str(), fd.get());
|
|
}
|
|
|
|
if (!fd.ok()) return -saved_errno;
|
|
|
|
// When reusing a pinned map, we need to check the map type/sizes/etc match, but for
|
|
// safety (since reuse code path is rare) run these checks even if we just created it.
|
|
// We assume failure is due to pinned map mismatch, hence the 'NOT UNIQUE' return code.
|
|
if (!mapMatchesExpectations(fd, mapNames[i], md[i], type)) return -ENOTUNIQ;
|
|
|
|
if (!reuse) {
|
|
if (specified(selinux_context)) {
|
|
string createLoc = string(BPF_FS_PATH) + lookupPinSubdir(selinux_context) +
|
|
"tmp_map_" + fname + "_" + mapNames[i];
|
|
ret = bpf_obj_pin(fd, createLoc.c_str());
|
|
if (ret) {
|
|
int err = errno;
|
|
ALOGE("create %s -> %d [%d:%s]", createLoc.c_str(), ret, err, strerror(err));
|
|
return -err;
|
|
}
|
|
ret = rename(createLoc.c_str(), mapPinLoc.c_str());
|
|
if (ret) {
|
|
int err = errno;
|
|
ALOGE("rename %s %s -> %d [%d:%s]", createLoc.c_str(), mapPinLoc.c_str(), ret,
|
|
err, strerror(err));
|
|
return -err;
|
|
}
|
|
} else {
|
|
ret = bpf_obj_pin(fd, mapPinLoc.c_str());
|
|
if (ret) return -errno;
|
|
}
|
|
ret = chown(mapPinLoc.c_str(), (uid_t)md[i].uid, (gid_t)md[i].gid);
|
|
if (ret) {
|
|
int err = errno;
|
|
ALOGE("chown(%s, %u, %u) = %d [%d:%s]", mapPinLoc.c_str(), md[i].uid, md[i].gid,
|
|
ret, err, strerror(err));
|
|
return -err;
|
|
}
|
|
ret = chmod(mapPinLoc.c_str(), md[i].mode);
|
|
if (ret) {
|
|
int err = errno;
|
|
ALOGE("chmod(%s, 0%o) = %d [%d:%s]", mapPinLoc.c_str(), md[i].mode, ret, err,
|
|
strerror(err));
|
|
return -err;
|
|
}
|
|
}
|
|
|
|
struct bpf_map_info map_info = {};
|
|
__u32 map_info_len = sizeof(map_info);
|
|
int rv = bpf_obj_get_info_by_fd(fd, &map_info, &map_info_len);
|
|
if (rv) {
|
|
ALOGE("bpf_obj_get_info_by_fd failed, ret: %d [%d]", rv, errno);
|
|
} else {
|
|
ALOGI("map %s id %d", mapPinLoc.c_str(), map_info.id);
|
|
}
|
|
|
|
mapFds.push_back(std::move(fd));
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* For debugging, dump all instructions */
|
|
static void dumpIns(char* ins, int size) {
|
|
for (int row = 0; row < size / 8; row++) {
|
|
ALOGE("%d: ", row);
|
|
for (int j = 0; j < 8; j++) {
|
|
ALOGE("%3x ", ins[(row * 8) + j]);
|
|
}
|
|
ALOGE("\n");
|
|
}
|
|
}
|
|
|
|
/* For debugging, dump all code sections from cs list */
|
|
static void dumpAllCs(vector<codeSection>& cs) {
|
|
for (int i = 0; i < (int)cs.size(); i++) {
|
|
ALOGE("Dumping cs %d, name %s", int(i), cs[i].name.c_str());
|
|
dumpIns((char*)cs[i].data.data(), cs[i].data.size());
|
|
ALOGE("-----------");
|
|
}
|
|
}
|
|
|
|
static void applyRelo(void* insnsPtr, Elf64_Addr offset, int fd) {
|
|
int insnIndex;
|
|
struct bpf_insn *insn, *insns;
|
|
|
|
insns = (struct bpf_insn*)(insnsPtr);
|
|
|
|
insnIndex = offset / sizeof(struct bpf_insn);
|
|
insn = &insns[insnIndex];
|
|
|
|
ALOGD(
|
|
"applying relo to instruction at byte offset: %d, \
|
|
insn offset %d , insn %lx\n",
|
|
(int)offset, (int)insnIndex, *(unsigned long*)insn);
|
|
|
|
if (insn->code != (BPF_LD | BPF_IMM | BPF_DW)) {
|
|
ALOGE("Dumping all instructions till ins %d", insnIndex);
|
|
ALOGE("invalid relo for insn %d: code 0x%x", insnIndex, insn->code);
|
|
dumpIns((char*)insnsPtr, (insnIndex + 3) * 8);
|
|
return;
|
|
}
|
|
|
|
insn->imm = fd;
|
|
insn->src_reg = BPF_PSEUDO_MAP_FD;
|
|
}
|
|
|
|
static void applyMapRelo(ifstream& elfFile, vector<unique_fd> &mapFds, vector<codeSection>& cs) {
|
|
vector<string> mapNames;
|
|
|
|
int ret = getSectionSymNames(elfFile, "maps", mapNames);
|
|
if (ret) return;
|
|
|
|
for (int k = 0; k != (int)cs.size(); k++) {
|
|
Elf64_Rel* rel = (Elf64_Rel*)(cs[k].rel_data.data());
|
|
int n_rel = cs[k].rel_data.size() / sizeof(*rel);
|
|
|
|
for (int i = 0; i < n_rel; i++) {
|
|
int symIndex = ELF64_R_SYM(rel[i].r_info);
|
|
string symName;
|
|
|
|
ret = getSymNameByIdx(elfFile, symIndex, symName);
|
|
if (ret) return;
|
|
|
|
/* Find the map fd and apply relo */
|
|
for (int j = 0; j < (int)mapNames.size(); j++) {
|
|
if (!mapNames[j].compare(symName)) {
|
|
applyRelo(cs[k].data.data(), rel[i].r_offset, mapFds[j]);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static int loadCodeSections(const char* elfPath, vector<codeSection>& cs, const string& license,
|
|
const char* prefix, const unsigned long long allowedDomainBitmask) {
|
|
unsigned kvers = kernelVersion();
|
|
int ret, fd;
|
|
|
|
if (!kvers) return -1;
|
|
|
|
string fname = pathToFilename(string(elfPath), true);
|
|
|
|
for (int i = 0; i < (int)cs.size(); i++) {
|
|
string name = cs[i].name;
|
|
unsigned bpfMinVer = DEFAULT_BPFLOADER_MIN_VER; // v0.0
|
|
unsigned bpfMaxVer = DEFAULT_BPFLOADER_MAX_VER; // v1.0
|
|
domain selinux_context = domain::unspecified;
|
|
domain pin_subdir = domain::unspecified;
|
|
|
|
if (cs[i].prog_def.has_value()) {
|
|
unsigned min_kver = cs[i].prog_def->min_kver;
|
|
unsigned max_kver = cs[i].prog_def->max_kver;
|
|
ALOGD("cs[%d].name:%s min_kver:%x .max_kver:%x (kvers:%x)", i, name.c_str(), min_kver,
|
|
max_kver, kvers);
|
|
if (kvers < min_kver) continue;
|
|
if (kvers >= max_kver) continue;
|
|
|
|
bpfMinVer = cs[i].prog_def->bpfloader_min_ver;
|
|
bpfMaxVer = cs[i].prog_def->bpfloader_max_ver;
|
|
selinux_context = getDomainFromSelinuxContext(cs[i].prog_def->selinux_context);
|
|
pin_subdir = getDomainFromPinSubdir(cs[i].prog_def->pin_subdir);
|
|
// Note: make sure to only check for unrecognized *after* verifying bpfloader
|
|
// version limits include this bpfloader's version.
|
|
}
|
|
|
|
ALOGD("cs[%d].name:%s requires bpfloader version [0x%05x,0x%05x)", i, name.c_str(),
|
|
bpfMinVer, bpfMaxVer);
|
|
if (BPFLOADER_VERSION < bpfMinVer) continue;
|
|
if (BPFLOADER_VERSION >= bpfMaxVer) continue;
|
|
if (unrecognized(pin_subdir)) return -ENOTDIR;
|
|
|
|
if (specified(selinux_context)) {
|
|
if (!inDomainBitmask(selinux_context, allowedDomainBitmask)) {
|
|
ALOGE("prog %s has invalid selinux_context of %d (allowed bitmask 0x%llx)",
|
|
name.c_str(), selinux_context, allowedDomainBitmask);
|
|
return -EINVAL;
|
|
}
|
|
ALOGI("prog %s selinux_context [%32s] -> %d -> '%s' (%s)", name.c_str(),
|
|
cs[i].prog_def->selinux_context, selinux_context,
|
|
lookupSelinuxContext(selinux_context), lookupPinSubdir(selinux_context));
|
|
}
|
|
|
|
if (specified(pin_subdir)) {
|
|
if (!inDomainBitmask(pin_subdir, allowedDomainBitmask)) {
|
|
ALOGE("prog %s has invalid pin_subdir of %d (allowed bitmask 0x%llx)", name.c_str(),
|
|
pin_subdir, allowedDomainBitmask);
|
|
return -EINVAL;
|
|
}
|
|
ALOGI("prog %s pin_subdir [%32s] -> %d -> '%s'", name.c_str(),
|
|
cs[i].prog_def->pin_subdir, pin_subdir, lookupPinSubdir(pin_subdir));
|
|
}
|
|
|
|
// strip any potential $foo suffix
|
|
// this can be used to provide duplicate programs
|
|
// conditionally loaded based on running kernel version
|
|
name = name.substr(0, name.find_last_of('$'));
|
|
|
|
bool reuse = false;
|
|
// Format of pin location is
|
|
// /sys/fs/bpf/<prefix>prog_<filename>_<mapname>
|
|
string progPinLoc = string(BPF_FS_PATH) + lookupPinSubdir(pin_subdir, prefix) + "prog_" +
|
|
fname + '_' + string(name);
|
|
if (access(progPinLoc.c_str(), F_OK) == 0) {
|
|
fd = retrieveProgram(progPinLoc.c_str());
|
|
ALOGD("New bpf prog load reusing prog %s, ret: %d (%s)", progPinLoc.c_str(), fd,
|
|
(fd < 0 ? std::strerror(errno) : "no error"));
|
|
reuse = true;
|
|
} else {
|
|
vector<char> log_buf(BPF_LOAD_LOG_SZ, 0);
|
|
|
|
struct bpf_load_program_attr attr = {
|
|
.prog_type = cs[i].type,
|
|
.name = name.c_str(),
|
|
.insns = (struct bpf_insn*)cs[i].data.data(),
|
|
.license = license.c_str(),
|
|
.log_level = 0,
|
|
.expected_attach_type = cs[i].expected_attach_type,
|
|
};
|
|
|
|
fd = bcc_prog_load_xattr(&attr, cs[i].data.size(), log_buf.data(), log_buf.size(),
|
|
true);
|
|
|
|
ALOGD("bpf_prog_load lib call for %s (%s) returned fd: %d (%s)", elfPath,
|
|
cs[i].name.c_str(), fd, (fd < 0 ? std::strerror(errno) : "no error"));
|
|
|
|
if (fd < 0) {
|
|
vector<string> lines = android::base::Split(log_buf.data(), "\n");
|
|
|
|
ALOGW("bpf_prog_load - BEGIN log_buf contents:");
|
|
for (const auto& line : lines) ALOGW("%s", line.c_str());
|
|
ALOGW("bpf_prog_load - END log_buf contents.");
|
|
|
|
if (cs[i].prog_def->optional) {
|
|
ALOGW("failed program is marked optional - continuing...");
|
|
continue;
|
|
}
|
|
ALOGE("non-optional program failed to load.");
|
|
}
|
|
}
|
|
|
|
if (fd < 0) return fd;
|
|
if (fd == 0) return -EINVAL;
|
|
|
|
if (!reuse) {
|
|
if (specified(selinux_context)) {
|
|
string createLoc = string(BPF_FS_PATH) + lookupPinSubdir(selinux_context) +
|
|
"tmp_prog_" + fname + '_' + string(name);
|
|
ret = bpf_obj_pin(fd, createLoc.c_str());
|
|
if (ret) {
|
|
int err = errno;
|
|
ALOGE("create %s -> %d [%d:%s]", createLoc.c_str(), ret, err, strerror(err));
|
|
return -err;
|
|
}
|
|
ret = rename(createLoc.c_str(), progPinLoc.c_str());
|
|
if (ret) {
|
|
int err = errno;
|
|
ALOGE("rename %s %s -> %d [%d:%s]", createLoc.c_str(), progPinLoc.c_str(), ret,
|
|
err, strerror(err));
|
|
return -err;
|
|
}
|
|
} else {
|
|
ret = bpf_obj_pin(fd, progPinLoc.c_str());
|
|
if (ret) {
|
|
int err = errno;
|
|
ALOGE("create %s -> %d [%d:%s]", progPinLoc.c_str(), ret, err, strerror(err));
|
|
return -err;
|
|
}
|
|
}
|
|
if (chmod(progPinLoc.c_str(), 0440)) {
|
|
int err = errno;
|
|
ALOGE("chmod %s 0440 -> [%d:%s]", progPinLoc.c_str(), err, strerror(err));
|
|
return -err;
|
|
}
|
|
if (cs[i].prog_def.has_value()) {
|
|
if (chown(progPinLoc.c_str(), (uid_t)cs[i].prog_def->uid,
|
|
(gid_t)cs[i].prog_def->gid)) {
|
|
int err = errno;
|
|
ALOGE("chown %s %d %d -> [%d:%s]", progPinLoc.c_str(), cs[i].prog_def->uid,
|
|
cs[i].prog_def->gid, err, strerror(err));
|
|
return -err;
|
|
}
|
|
}
|
|
}
|
|
|
|
struct bpf_prog_info prog_info = {};
|
|
__u32 prog_info_len = sizeof(prog_info);
|
|
int rv = bpf_obj_get_info_by_fd(fd, &prog_info, &prog_info_len);
|
|
if (rv) {
|
|
ALOGE("bpf_obj_get_info_by_fd failed, ret: %d [%d]", rv, errno);
|
|
} else {
|
|
ALOGI("prog %s id %d", progPinLoc.c_str(), prog_info.id);
|
|
}
|
|
|
|
cs[i].prog_fd.reset(fd);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int loadProg(const char* elfPath, bool* isCritical, const char* prefix,
|
|
const unsigned long long allowedDomainBitmask, const bpf_prog_type* allowed,
|
|
size_t numAllowed) {
|
|
vector<char> license;
|
|
vector<char> critical;
|
|
vector<codeSection> cs;
|
|
vector<unique_fd> mapFds;
|
|
int ret;
|
|
|
|
if (!isCritical) return -1;
|
|
*isCritical = false;
|
|
|
|
ifstream elfFile(elfPath, ios::in | ios::binary);
|
|
if (!elfFile.is_open()) return -1;
|
|
|
|
ret = readSectionByName("critical", elfFile, critical);
|
|
*isCritical = !ret;
|
|
|
|
ret = readSectionByName("license", elfFile, license);
|
|
if (ret) {
|
|
ALOGE("Couldn't find license in %s", elfPath);
|
|
return ret;
|
|
} else {
|
|
ALOGD("Loading %s%s ELF object %s with license %s",
|
|
*isCritical ? "critical for " : "optional", *isCritical ? (char*)critical.data() : "",
|
|
elfPath, (char*)license.data());
|
|
}
|
|
|
|
// the following default values are for bpfloader V0.0 format which does not include them
|
|
unsigned int bpfLoaderMinVer =
|
|
readSectionUint("bpfloader_min_ver", elfFile, DEFAULT_BPFLOADER_MIN_VER);
|
|
unsigned int bpfLoaderMaxVer =
|
|
readSectionUint("bpfloader_max_ver", elfFile, DEFAULT_BPFLOADER_MAX_VER);
|
|
size_t sizeOfBpfMapDef =
|
|
readSectionUint("size_of_bpf_map_def", elfFile, DEFAULT_SIZEOF_BPF_MAP_DEF);
|
|
size_t sizeOfBpfProgDef =
|
|
readSectionUint("size_of_bpf_prog_def", elfFile, DEFAULT_SIZEOF_BPF_PROG_DEF);
|
|
|
|
// inclusive lower bound check
|
|
if (BPFLOADER_VERSION < bpfLoaderMinVer) {
|
|
ALOGI("BpfLoader version 0x%05x ignoring ELF object %s with min ver 0x%05x",
|
|
BPFLOADER_VERSION, elfPath, bpfLoaderMinVer);
|
|
return 0;
|
|
}
|
|
|
|
// exclusive upper bound check
|
|
if (BPFLOADER_VERSION >= bpfLoaderMaxVer) {
|
|
ALOGI("BpfLoader version 0x%05x ignoring ELF object %s with max ver 0x%05x",
|
|
BPFLOADER_VERSION, elfPath, bpfLoaderMaxVer);
|
|
return 0;
|
|
}
|
|
|
|
ALOGI("BpfLoader version 0x%05x processing ELF object %s with ver [0x%05x,0x%05x)",
|
|
BPFLOADER_VERSION, elfPath, bpfLoaderMinVer, bpfLoaderMaxVer);
|
|
|
|
if (sizeOfBpfMapDef < DEFAULT_SIZEOF_BPF_MAP_DEF) {
|
|
ALOGE("sizeof(bpf_map_def) of %zu is too small (< %d)", sizeOfBpfMapDef,
|
|
DEFAULT_SIZEOF_BPF_MAP_DEF);
|
|
return -1;
|
|
}
|
|
|
|
if (sizeOfBpfProgDef < DEFAULT_SIZEOF_BPF_PROG_DEF) {
|
|
ALOGE("sizeof(bpf_prog_def) of %zu is too small (< %d)", sizeOfBpfProgDef,
|
|
DEFAULT_SIZEOF_BPF_PROG_DEF);
|
|
return -1;
|
|
}
|
|
|
|
ret = readCodeSections(elfFile, cs, sizeOfBpfProgDef, allowed, numAllowed);
|
|
if (ret) {
|
|
ALOGE("Couldn't read all code sections in %s", elfPath);
|
|
return ret;
|
|
}
|
|
|
|
/* Just for future debugging */
|
|
if (0) dumpAllCs(cs);
|
|
|
|
ret = createMaps(elfPath, elfFile, mapFds, prefix, allowedDomainBitmask, sizeOfBpfMapDef);
|
|
if (ret) {
|
|
ALOGE("Failed to create maps: (ret=%d) in %s", ret, elfPath);
|
|
return ret;
|
|
}
|
|
|
|
for (int i = 0; i < (int)mapFds.size(); i++)
|
|
ALOGD("map_fd found at %d is %d in %s", i, mapFds[i].get(), elfPath);
|
|
|
|
applyMapRelo(elfFile, mapFds, cs);
|
|
|
|
ret = loadCodeSections(elfPath, cs, string(license.data()), prefix, allowedDomainBitmask);
|
|
if (ret) ALOGE("Failed to load programs, loadCodeSections ret=%d", ret);
|
|
|
|
return ret;
|
|
}
|
|
|
|
} // namespace bpf
|
|
} // namespace android
|