blob: d810928f784caaf200819e324b7b15b536e46e5b [file] [log] [blame]
/* Copyright (c) 2014, Google Inc.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
#include <openssl/base.h>
#include <memory>
#include <string>
#include <vector>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <stdio.h>
#include <sys/stat.h>
#include <sys/types.h>
#if !defined(OPENSSL_WINDOWS)
#include <string.h>
#include <unistd.h>
#if !defined(O_BINARY)
#define O_BINARY 0
#endif
#else
OPENSSL_MSVC_PRAGMA(warning(push, 3))
#include <windows.h>
OPENSSL_MSVC_PRAGMA(warning(pop))
#include <io.h>
#if !defined(PATH_MAX)
#define PATH_MAX MAX_PATH
#endif
#endif
#include <openssl/digest.h>
#include "internal.h"
// Source is an awkward expression of a union type in C++: Stdin | File filename.
struct Source {
enum Type {
STDIN,
};
Source() : is_stdin_(false) {}
explicit Source(Type) : is_stdin_(true) {}
explicit Source(const std::string &name)
: is_stdin_(false), filename_(name) {}
bool is_stdin() const { return is_stdin_; }
const std::string &filename() const { return filename_; }
private:
bool is_stdin_;
std::string filename_;
};
static const char kStdinName[] = "standard input";
// OpenFile opens the regular file named |filename| and returns a file
// descriptor to it.
static ScopedFD OpenFile(const std::string &filename) {
ScopedFD fd = OpenFD(filename.c_str(), O_RDONLY | O_BINARY);
if (!fd) {
fprintf(stderr, "Failed to open input file '%s': %s\n", filename.c_str(),
strerror(errno));
return ScopedFD();
}
#if !defined(OPENSSL_WINDOWS)
struct stat st;
if (fstat(fd.get(), &st)) {
fprintf(stderr, "Failed to stat input file '%s': %s\n", filename.c_str(),
strerror(errno));
return ScopedFD();
}
if (!S_ISREG(st.st_mode)) {
fprintf(stderr, "%s: not a regular file\n", filename.c_str());
return ScopedFD();
}
#endif
return fd;
}
// SumFile hashes the contents of |source| with |md| and sets |*out_hex| to the
// hex-encoded result.
//
// It returns true on success or prints an error to stderr and returns false on
// error.
static bool SumFile(std::string *out_hex, const EVP_MD *md,
const Source &source) {
ScopedFD scoped_fd;
int fd;
if (source.is_stdin()) {
fd = 0;
} else {
scoped_fd = OpenFile(source.filename());
if (!scoped_fd) {
return false;
}
fd = scoped_fd.get();
}
static const size_t kBufSize = 8192;
std::unique_ptr<uint8_t[]> buf(new uint8_t[kBufSize]);
bssl::ScopedEVP_MD_CTX ctx;
if (!EVP_DigestInit_ex(ctx.get(), md, NULL)) {
fprintf(stderr, "Failed to initialize EVP_MD_CTX.\n");
return false;
}
for (;;) {
size_t n;
if (!ReadFromFD(fd, &n, buf.get(), kBufSize)) {
fprintf(stderr, "Failed to read from %s: %s\n",
source.is_stdin() ? kStdinName : source.filename().c_str(),
strerror(errno));
return false;
}
if (n == 0) {
break;
}
if (!EVP_DigestUpdate(ctx.get(), buf.get(), n)) {
fprintf(stderr, "Failed to update hash.\n");
return false;
}
}
uint8_t digest[EVP_MAX_MD_SIZE];
unsigned digest_len;
if (!EVP_DigestFinal_ex(ctx.get(), digest, &digest_len)) {
fprintf(stderr, "Failed to finish hash.\n");
return false;
}
char hex_digest[EVP_MAX_MD_SIZE * 2];
static const char kHextable[] = "0123456789abcdef";
for (unsigned i = 0; i < digest_len; i++) {
const uint8_t b = digest[i];
hex_digest[i * 2] = kHextable[b >> 4];
hex_digest[i * 2 + 1] = kHextable[b & 0xf];
}
*out_hex = std::string(hex_digest, digest_len * 2);
return true;
}
// PrintFileSum hashes |source| with |md| and prints a line to stdout in the
// format of the coreutils *sum utilities. It returns true on success or prints
// an error to stderr and returns false on error.
static bool PrintFileSum(const EVP_MD *md, const Source &source) {
std::string hex_digest;
if (!SumFile(&hex_digest, md, source)) {
return false;
}
// TODO: When given "--binary" or "-b", we should print " *" instead of " "
// between the digest and the filename.
//
// MSYS and Cygwin md5sum default to binary mode by default, whereas other
// platforms' tools default to text mode by default. We default to text mode
// by default and consider text mode equivalent to binary mode (i.e. we
// always use Unix semantics, even on Windows), which means that our default
// output will differ from the MSYS and Cygwin tools' default output.
printf("%s %s\n", hex_digest.c_str(),
source.is_stdin() ? "-" : source.filename().c_str());
return true;
}
// CheckModeArguments contains arguments for the check mode. See the
// sha256sum(1) man page for details.
struct CheckModeArguments {
bool quiet = false;
bool status = false;
bool warn = false;
bool strict = false;
};
// Check reads lines from |source| where each line is in the format of the
// coreutils *sum utilities. It attempts to verify each hash by reading the
// file named in the line.
//
// It returns true if all files were verified and, if |args.strict|, no input
// lines had formatting errors. Otherwise it prints errors to stderr and
// returns false.
static bool Check(const CheckModeArguments &args, const EVP_MD *md,
const Source &source) {
FILE *file;
ScopedFILE scoped_file;
if (source.is_stdin()) {
file = stdin;
} else {
ScopedFD fd = OpenFile(source.filename());
if (!fd) {
return false;
}
scoped_file = FDToFILE(std::move(fd), "rb");
if (!scoped_file) {
perror("fdopen");
return false;
}
file = scoped_file.get();
}
const size_t hex_size = EVP_MD_size(md) * 2;
char line[EVP_MAX_MD_SIZE * 2 + 2 /* spaces */ + PATH_MAX + 1 /* newline */ +
1 /* NUL */];
unsigned bad_lines = 0;
unsigned parsed_lines = 0;
unsigned error_lines = 0;
unsigned line_no = 0;
bool ok = true;
bool draining_overlong_line = false;
for (;;) {
line_no++;
if (fgets(line, sizeof(line), file) == nullptr) {
if (feof(file)) {
break;
}
fprintf(stderr, "Error reading from input.\n");
return false;
}
size_t len = strlen(line);
if (draining_overlong_line) {
if (line[len - 1] == '\n') {
draining_overlong_line = false;
}
continue;
}
const bool overlong = line[len - 1] != '\n' && !feof(file);
if (len < hex_size + 2 /* spaces */ + 1 /* filename */ ||
line[hex_size] != ' ' ||
line[hex_size + 1] != ' ' ||
overlong) {
bad_lines++;
if (args.warn) {
fprintf(stderr, "%s: %u: improperly formatted line\n",
source.is_stdin() ? kStdinName : source.filename().c_str(), line_no);
}
if (args.strict) {
ok = false;
}
if (overlong) {
draining_overlong_line = true;
}
continue;
}
if (line[len - 1] == '\n') {
line[len - 1] = 0;
len--;
}
parsed_lines++;
// coreutils does not attempt to restrict relative or absolute paths in the
// input so nor does this code.
std::string calculated_hex_digest;
const std::string target_filename(&line[hex_size + 2]);
Source target_source;
if (target_filename == "-") {
// coreutils reads from stdin if the filename is "-".
target_source = Source(Source::STDIN);
} else {
target_source = Source(target_filename);
}
if (!SumFile(&calculated_hex_digest, md, target_source)) {
error_lines++;
ok = false;
continue;
}
if (calculated_hex_digest != std::string(line, hex_size)) {
if (!args.status) {
printf("%s: FAILED\n", target_filename.c_str());
}
ok = false;
continue;
}
if (!args.quiet) {
printf("%s: OK\n", target_filename.c_str());
}
}
if (!args.status) {
if (bad_lines > 0 && parsed_lines > 0) {
fprintf(stderr, "WARNING: %u line%s improperly formatted\n", bad_lines,
bad_lines == 1 ? " is" : "s are");
}
if (error_lines > 0) {
fprintf(stderr, "WARNING: %u computed checksum(s) did NOT match\n",
error_lines);
}
}
if (parsed_lines == 0) {
fprintf(stderr, "%s: no properly formatted checksum lines found.\n",
source.is_stdin() ? kStdinName : source.filename().c_str());
ok = false;
}
return ok;
}
// DigestSum acts like the coreutils *sum utilites, with the given hash
// function.
static bool DigestSum(const EVP_MD *md,
const std::vector<std::string> &args) {
bool check_mode = false;
CheckModeArguments check_args;
bool check_mode_args_given = false;
std::vector<Source> sources;
auto it = args.begin();
while (it != args.end()) {
const std::string &arg = *it;
if (!arg.empty() && arg[0] != '-') {
break;
}
it++;
if (arg == "--") {
break;
}
if (arg == "-") {
// "-" ends the argument list and indicates that stdin should be used.
sources.push_back(Source(Source::STDIN));
break;
}
if (arg.size() >= 2 && arg[0] == '-' && arg[1] != '-') {
for (size_t i = 1; i < arg.size(); i++) {
switch (arg[i]) {
case 'b':
case 't':
// Binary/text mode – irrelevent, even on Windows.
break;
case 'c':
check_mode = true;
break;
case 'w':
check_mode_args_given = true;
check_args.warn = true;
break;
default:
fprintf(stderr, "Unknown option '%c'.\n", arg[i]);
return false;
}
}
} else if (arg == "--binary" || arg == "--text") {
// Binary/text mode – irrelevent, even on Windows.
} else if (arg == "--check") {
check_mode = true;
} else if (arg == "--quiet") {
check_mode_args_given = true;
check_args.quiet = true;
} else if (arg == "--status") {
check_mode_args_given = true;
check_args.status = true;
} else if (arg == "--warn") {
check_mode_args_given = true;
check_args.warn = true;
} else if (arg == "--strict") {
check_mode_args_given = true;
check_args.strict = true;
} else {
fprintf(stderr, "Unknown option '%s'.\n", arg.c_str());
return false;
}
}
if (check_mode_args_given && !check_mode) {
fprintf(
stderr,
"Check mode arguments are only meaningful when verifying checksums.\n");
return false;
}
for (; it != args.end(); it++) {
sources.push_back(Source(*it));
}
if (sources.empty()) {
sources.push_back(Source(Source::STDIN));
}
bool ok = true;
if (check_mode) {
for (auto &source : sources) {
ok &= Check(check_args, md, source);
}
} else {
for (auto &source : sources) {
ok &= PrintFileSum(md, source);
}
}
return ok;
}
bool MD5Sum(const std::vector<std::string> &args) {
return DigestSum(EVP_md5(), args);
}
bool SHA1Sum(const std::vector<std::string> &args) {
return DigestSum(EVP_sha1(), args);
}
bool SHA224Sum(const std::vector<std::string> &args) {
return DigestSum(EVP_sha224(), args);
}
bool SHA256Sum(const std::vector<std::string> &args) {
return DigestSum(EVP_sha256(), args);
}
bool SHA384Sum(const std::vector<std::string> &args) {
return DigestSum(EVP_sha384(), args);
}
bool SHA512Sum(const std::vector<std::string> &args) {
return DigestSum(EVP_sha512(), args);
}
bool SHA512256Sum(const std::vector<std::string> &args) {
return DigestSum(EVP_sha512_256(), args);
}