diff options
Diffstat (limited to 'common.c')
-rw-r--r-- | common.c | 526 |
1 files changed, 526 insertions, 0 deletions
diff --git a/common.c b/common.c new file mode 100644 index 0000000..580ca72 --- /dev/null +++ b/common.c @@ -0,0 +1,526 @@ +/* See LICENSE file for copyright and license details. */ +#include "common.h" + +#include <sys/stat.h> +#include <alloca.h> +#include <errno.h> +#include <fcntl.h> +#include <stddef.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + + + +#ifndef STDIN_PATH +# ifndef DEVDIR +# define DEVDIR "/dev" +# endif +# define STDIN_PATH DEVDIR"/stdin" +#endif + + + +#define USER_ERROR(string)\ + (fprintf(stderr, "%s: %s.\n", execname, string), 1) + +#define ADD(arg, desc, ...)\ + (arg ? args_add_option(args_new_argumented(NULL, arg, 0, __VA_ARGS__, NULL), desc)\ + : args_add_option(args_new_argumentless(NULL, 0, __VA_ARGS__, NULL), desc)) + +#define LAST(arg)\ + (args_opts_get(arg)[args_opts_get_count(arg) - 1]) + + + +/** + * Storage for binary hash + */ +static char *restrict hashsum = NULL; + +/** + * Storage for hexadecimal hash + */ +static char *restrict hexsum = NULL; + +/** + * Storage for binary version of expected checksum + */ +#define correct_binary hexsum + +/** + * Whether a mismatch has been found or if a file was missing + */ +static int bad_found = 0; + +/** + * `argv[0]` from `main` + */ +static char *execname; + + + +/** + * Calculate a Keccak-family hashsum of a file, + * the content of the file is assumed non-sensitive + * + * @param fd The file descriptor of the file to hash + * @param state The hashing state, should not be initialised (memory leak otherwise) + * @param spec Specifications for the hashing algorithm + * @param suffix The data suffix, see `libkeccak_digest` + * @param hash Output array for the hashsum, have an allocation size of + * at least `(spec->output / 8) * sizeof(char)`, may be `NULL` + * @return Zero on success, -1 on error + */ +static int +generalised_sum_fd_hex(int fd, libkeccak_state_t *restrict state, + const libkeccak_spec_t *restrict spec, + const char *restrict suffix, char *restrict hash) +{ + ssize_t got; + struct stat attr; + size_t blksize = 4096, r_ptr = 0, w_ptr = 0; + char *restrict chunk; + char even = 1, buf = 0, c; + + if (libkeccak_state_initialise(state, spec) < 0) + return -1; + + if (fstat(fd, &attr) == 0) + if (attr.st_blksize > 0) + blksize = (size_t)(attr.st_blksize); + + chunk = alloca(blksize); + + for (;;) { + got = read(fd, chunk, blksize); + if (got < 0) return -1; + if (!got) break; + while (r_ptr < (size_t)got) { + if (c = chunk[r_ptr++], c <= ' ') + continue; + buf = (buf << 4) | ((c & 15) + (c > '9' ? 9 : 0)); + if ((even ^= 1)) + chunk[w_ptr++] = buf; + } + if (libkeccak_fast_update(state, chunk, w_ptr) < 0) + return -1; + } + + return libkeccak_fast_digest(state, NULL, 0, 0, suffix, hash); +} + + +/** + * Convert `libkeccak_generalised_spec_t` to `libkeccak_spec_t` and check for errors + * + * @param gspec See `libkeccak_degeneralise_spec` + * @param spec See `libkeccak_degeneralise_spec` + * @return Zero on success, an appropriate exit value on error + */ +static int +make_spec(libkeccak_generalised_spec_t *restrict gspec, libkeccak_spec_t *restrict spec) +{ + int r; + +#define TEST(CASE, STR) case LIBKECCAK_GENERALISED_SPEC_ERROR_##CASE: return USER_ERROR(STR) + if (r = libkeccak_degeneralise_spec(gspec, spec), r) { + switch (r) { + TEST (STATE_NONPOSITIVE, "the state size must be positive"); + TEST (STATE_TOO_LARGE, "the state size is too large, may not exceed 1600"); + TEST (STATE_MOD_25, "the state size must be a multiple of 25"); + TEST (WORD_NONPOSITIVE, "the word size must be positive"); + TEST (WORD_TOO_LARGE, "the word size is too large, may not exceed 64"); + TEST (STATE_WORD_INCOHERENCY, "the state size must be exactly 25 times the word size"); + TEST (CAPACITY_NONPOSITIVE, "the capacity must be positive"); + TEST (CAPACITY_MOD_8, "the capacity must be a multiple of 8"); + TEST (BITRATE_NONPOSITIVE, "the rate must be positive"); + TEST (BITRATE_MOD_8, "the rate must be a multiple of 8"); + TEST (OUTPUT_NONPOSITIVE, "the output size must be positive"); + default: + return USER_ERROR("unknown error in algorithm parameters"); + } + } +#undef TEST + +#define TEST(CASE, STR) case LIBKECCAK_SPEC_ERROR_##CASE: return USER_ERROR(STR) + if (r = libkeccak_spec_check(spec), r) { + switch (r) { + TEST (BITRATE_NONPOSITIVE, "the rate size must be positive"); + TEST (BITRATE_MOD_8, "the rate must be a multiple of 8"); + TEST (CAPACITY_NONPOSITIVE, "the capacity must be positive"); + TEST (CAPACITY_MOD_8, "the capacity must be a multiple of 8"); + TEST (OUTPUT_NONPOSITIVE, "the output size must be positive"); + TEST (STATE_TOO_LARGE, "the state size is too large, may not exceed 1600"); + TEST (STATE_MOD_25, "the state size must be a multiple of 25"); + TEST (WORD_NON_2_POTENT, "the word size must be a power of 2"); + TEST (WORD_MOD_8, "the word size must be a multiple of 8"); + default: + return USER_ERROR("unknown error in algorithm parameters"); + } + } +#undef TEST + + return 0; +} + + +/** + * Calculate the checksum of a file and store it in the global variable `hashsum` + * + * @param filename The file to hash + * @param spec Hashing parameters + * @param squeezes The number of squeezes to perform + * @param suffix The message suffix + * @param hex Whether to use hexadecimal input rather than binary + * @return Zero on success, an appropriate exit value on error + */ +static int +hash(const char *restrict filename, const libkeccak_spec_t *restrict spec, + long squeezes, const char *restrict suffix, int hex) +{ + libkeccak_state_t state; + size_t length; + int r, fd; + + length = (size_t)((spec->output + 7) / 8); + + if (!hashsum && (hashsum = malloc(length * sizeof(char)), !hashsum)) + return perror(execname), 2; + + if (!hexsum && (hexsum = malloc((length * 2 + 1) * sizeof(char)), !hexsum)) + return perror(execname), 2; + + if (fd = open(strcmp(filename, "-") ? filename : STDIN_PATH, O_RDONLY), fd < 0) + return r = (errno != ENOENT), perror(execname), r + 1; + + if ((hex == 0 ? libkeccak_generalised_sum_fd : generalised_sum_fd_hex) + (fd, &state, spec, suffix, squeezes > 1 ? NULL : hashsum)) + return perror(execname), close(fd), libkeccak_state_fast_destroy(&state), 2; + close(fd); + + if (squeezes > 2) libkeccak_fast_squeeze(&state, squeezes - 2); + if (squeezes > 1) libkeccak_squeeze(&state, hashsum); + libkeccak_state_fast_destroy(&state); + + return 0; +} + + +/** + * Check that file has a reported checksum, `bad_found` will be + * updated if the file is missing or incorrect + * + * @param spec Hashing parameters + * @param squeezes The number of squeezes to perform + * @param suffix The message suffix + * @param hex Whether to use hexadecimal input rather than binary + * @param filename The file to check + * @param correct_hash The expected checksum (any form of hexadecimal) + * @return Zero on success, an appropriate exit value on error + */ +static int +check(const libkeccak_spec_t *restrict spec, long squeezes, const char *restrict suffix, + int hex, const char *restrict filename, const char *restrict correct_hash) +{ + size_t length = (size_t)((spec->output + 7) / 8); + int r; + + if (access(filename, F_OK)) { + bad_found = 1; + printf("%s: %s\n", filename, "Missing"); + return 0; + } + + if ((r = hash(filename, spec, squeezes, suffix, hex))) + return r; + + libkeccak_unhex(correct_binary, correct_hash); + if ((r = memcmp(correct_binary, hashsum, length))) + bad_found = 1; + printf("%s: %s\n", filename, !r ? "OK" : "Fail"); + + return 0; +} + + +/** + * Check checksums from a file + * + * @param filename The file to hash + * @param spec Hashing parameters + * @param squeezes The number of squeezes to perform + * @param suffix The message suffix + * @param representation (unused) + * @param hex Whether to use hexadecimal input rather than binary + * @return Zero on success, an appropriate exit value on error + */ +static int +check_checksums(const char *restrict filename, const libkeccak_spec_t *restrict spec, + long squeezes, const char *restrict suffix, int representation, int hex) +{ + struct stat attr; + size_t blksize = 4096; + size_t size = 4096; + size_t ptr = 0; + ssize_t got; + char *buf = NULL; + char *new; + int fd = -1, rc = 2, stage, r; + size_t hash_start = 0, hash_end = 0; + size_t file_start = 0, file_end = 0; + char *hash; + char *file; + size_t hash_n; + char c; + + if (fd = open(strcmp(filename, "-") ? filename : STDIN_PATH, O_RDONLY), fd < 0) + goto pfail; + + if (fstat(fd, &attr) == 0) { + if (attr.st_blksize > 0) blksize = (size_t)(attr.st_blksize); + if (attr.st_size > 0) size = (size_t)(attr.st_size); + } + + size = size > blksize ? size : blksize; + if (buf = malloc(size), buf == NULL) + goto pfail; + + for (;;) { + if (ptr + blksize < size) { + if (new = realloc(buf, size <<= 1), new == NULL) + goto pfail; + buf = new; + } + + got = read(fd, buf + ptr, blksize); + if (got < 0) goto pfail; + else if (got == 0) break; + else ptr += (size_t)got; + } + if (ptr == size) { + if (new = realloc(buf, size + 1), new == NULL) + goto pfail; + buf = new; + } + size = ptr; + close(fd), fd = -1; + buf[size++] = '\n'; + + for (ptr = 0, stage = 0; ptr < size; ptr++) { + c = buf[ptr]; + if (stage == 0) { + if (('0' <= c) && (c <= '9')); + else if (('a' <= c) && (c <= 'f')); + else if (('A' <= c) && (c <= 'F')); + else if ((c == ' ') || (c == '\t')) { + hash_end = ptr, stage++; + } else if ((c == '\n') || (c == '\f') || (c == '\r')) { + hash_end = ptr, stage = 3; + } else { + rc = USER_ERROR("file is malformated"); + goto fail; + } + } else if (stage == 1) { + if ((c == '\n') || (c == '\f') || (c == '\r')) + stage = 3; + else if ((c != ' ') && (c != '\t')) + file_start = ptr, stage++; + } else if (stage == 2) { + if ((c == '\n') || (c == '\f') || (c == '\r')) + file_end = ptr, stage++; + } + + if (stage == 3) { + if ((hash_start == hash_end) != (file_start == file_end)) { + rc = USER_ERROR("file is malformated"); + goto fail; + } + if (hash_start != hash_end) { + hash = buf + hash_start; + file = buf + file_start; + hash_n = hash_end - hash_start; + buf[hash_end] = '\0'; + buf[file_end] = '\0'; + if (hash_n % 2) { + rc = USER_ERROR("file is malformated"); + goto fail; + } + if (hash_n / 2 != (size_t)((spec->output + 7) / 8)) { + rc = USER_ERROR("algorithm parameter mismatch"); + goto fail; + } + if ((r = check(spec, squeezes, suffix, hex, file, hash))) { + rc = r; + goto fail; + } + } + stage = 0; + hash_start = hash_end = file_start = file_end = ptr + 1; + } + } + + if (stage) { + rc = USER_ERROR("file is malformated"); + goto fail; + } + + free(buf); + return 0; + +pfail: + perror(execname); +fail: + free(buf); + if (fd >= 0) + close(fd); + return rc; + + (void) representation; +} + + +/** + * Print the checksum of a file + * + * @param filename The file to hash + * @param spec Hashing parameters + * @param squeezes The number of squeezes to perform + * @param suffix The message suffix + * @param representation Either of `REPRESENTATION_BINARY`, `REPRESENTATION_UPPER_CASE` + * and `REPRESENTATION_LOWER_CASE` + * @param hex Whether to use hexadecimal input rather than binary + * @return Zero on success, an appropriate exit value on error + */ +static int +print_checksum(const char *restrict filename, const libkeccak_spec_t *restrict spec, + long squeezes, const char *restrict suffix, int representation, int hex) +{ + size_t length = (size_t)((spec->output + 7) / 8); + int r; + size_t ptr = 0; + ssize_t wrote; + + if ((r = hash(filename, spec, squeezes, suffix, hex))) + return r; + + if (representation == REPRESENTATION_UPPER_CASE) { + libkeccak_behex_upper(hexsum, hashsum, length); + printf("%s %s\n", hexsum, filename); + } else if (representation == REPRESENTATION_LOWER_CASE) { + libkeccak_behex_lower(hexsum, hashsum, length); + printf("%s %s\n", hexsum, filename); + } else { + fflush(stdout); + while (length - ptr) { + wrote = write(STDOUT_FILENO, hashsum, length - ptr); + if (wrote <= 0) + return perror(execname), 2; + ptr += (size_t)wrote; + } + } + + return 0; +} + + +/** + * Cleanup allocations + */ +static inline void +cleanup(void) +{ + free(hashsum), hashsum = NULL; + free(hexsum), hexsum = NULL; +} + + +/** + * Parse the command line and calculate the hashes of the selected files + * + * @param argc The first argument from `main` + * @param argv The second argument from `main` + * @param gspec The default algorithm parameters + * @param suffix Message suffix + * @return An appropriate exit value + */ +int +run(int argc, char *argv[], libkeccak_generalised_spec_t *restrict gspec, const char *restrict suffix) +{ + int r, verbose = 0, presentation = REPRESENTATION_UPPER_CASE, hex = 0, check = 0; + long squeezes = 1; + size_t i; + libkeccak_spec_t spec; + int (*fun)(const char *restrict filename, const libkeccak_spec_t *restrict spec, + long squeezes, const char *restrict suffix, int representation, int hex); + + execname = *argv; + + ADD(NULL, "Display option summary", "-h", "--help"); + ADD("RATE", "Select rate", "-R", "--bitrate", "--rate"); + ADD("CAPACITY", "Select capacity", "-C", "--capacity"); + ADD("SIZE", "Select output size", "-N", "-O", "--output-size", "--output"); + ADD("SIZE", "Select state size", "-S", "-B", "--state-size", "--state"); + ADD("SIZE", "Select word size", "-W", "--word-size", "--word"); + ADD("COUNT", "Select squeeze count", "-Z", "--squeezes"); + ADD(NULL, "Use upper-case output", "-u", "--upper", "--uppercase", "--upper-case"); + ADD(NULL, "Use lower-case output", "-l", "--lower", "--lowercase", "--lower-case"); + ADD(NULL, "Use binary output", "-b", "--binary"); + ADD(NULL, "Use hexadecimal input", "-x", "--hex", "--hex-input"); + ADD(NULL, "Check checksums", "-c", "--check"); + ADD(NULL, "Be verbose", "-v", "--verbose"); + /* --check has been added because the sha1sum, sha256sum &c have it, + * but I ignore the other crap, mostly because not all implemention + * have them and binary vs text mode is stupid. */ + + args_parse(argc, argv); + + if (args_opts_used("-h")) return args_help(0), args_dispose(), 0; + if (args_opts_used("-R")) gspec->bitrate = atol(LAST("-R")); + if (args_opts_used("-C")) gspec->capacity = atol(LAST("-C")); + if (args_opts_used("-N")) gspec->output = atol(LAST("-N")); + if (args_opts_used("-S")) gspec->state_size = atol(LAST("-S")); + if (args_opts_used("-W")) gspec->word_size = atol(LAST("-W")); + if (args_opts_used("-Z")) squeezes = atol(LAST("-Z")); + if (args_opts_used("-u")) presentation = REPRESENTATION_UPPER_CASE; + if (args_opts_used("-l")) presentation = REPRESENTATION_LOWER_CASE; + if (args_opts_used("-b")) presentation = REPRESENTATION_BINARY; + if (args_opts_used("-x")) hex = 1; + if (args_opts_used("-c")) check = 1; + if (args_opts_used("-v")) verbose = 1; + + fun = check ? check_checksums : print_checksum; + + if ((r = make_spec(gspec, &spec))) + goto done; + + if (squeezes <= 0) { + r = USER_ERROR("the squeeze count most be positive"); + goto done; + } + + if (verbose) { + fprintf(stderr, "rate: %li\n", gspec->bitrate); + fprintf(stderr, "capacity: %li\n", gspec->capacity); + fprintf(stderr, "output size: %li\n", gspec->output); + fprintf(stderr, "state size: %li\n", gspec->state_size); + fprintf(stderr, "word size: %li\n", gspec->word_size); + fprintf(stderr, "squeezes: %li\n", squeezes); + fprintf(stderr, "suffix: %s\n", suffix ? suffix : ""); + } + + if (args_files_count == 0) { + r = fun("-", &spec, squeezes, suffix, presentation, hex); + } else { + for (i = 0; i < (size_t)args_files_count; i++) + if ((r = fun(args_files[i], &spec, squeezes, suffix, presentation, hex))) + break; + } + +done: + args_dispose(); + cleanup(); + return r ? r : bad_found; +} + |