source: MondoRescue/branches/2.2.5/mindi-busybox/coreutils/md5_sha1_sum.c@ 1765

/* vi: set sw=4 ts=4: */
/*
 *  Copyright (C) 2003 Glenn L. McGrath
 *  Copyright (C) 2003-2004 Erik Andersen
 *
 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
 */

#include "libbb.h"

typedef enum { HASH_SHA1, HASH_MD5 } hash_algo_t;

#define FLAG_SILENT 1
#define FLAG_CHECK  2
#define FLAG_WARN   4

/* This might be useful elsewhere */
static unsigned char *hash_bin_to_hex(unsigned char *hash_value,
                unsigned hash_length)
{
    /* xzalloc zero-terminates */
    char *hex_value = xzalloc((hash_length * 2) + 1);
    bin2hex(hex_value, (char*)hash_value, hash_length);
    return hex_value;
}

static uint8_t *hash_file(const char *filename, hash_algo_t hash_algo)
{
    int src_fd, hash_len, count;
    union _ctx_ {
        sha1_ctx_t sha1;
        md5_ctx_t md5;
    } context;
    uint8_t *hash_value = NULL;
    RESERVE_CONFIG_UBUFFER(in_buf, 4096);
    void (*update)(const void*, size_t, void*);
    void (*final)(void*, void*);

    src_fd = STDIN_FILENO;
    if (NOT_LONE_DASH(filename)) {
        src_fd = open_or_warn(filename, O_RDONLY);
        if (src_fd < 0) {
            return NULL;
        }
    }

    /* figure specific hash algorithims */
    if (ENABLE_MD5SUM && hash_algo==HASH_MD5) {
        md5_begin(&context.md5);
        update = (void (*)(const void*, size_t, void*))md5_hash;
        final = (void (*)(void*, void*))md5_end;
        hash_len = 16;
    } else if (ENABLE_SHA1SUM && hash_algo==HASH_SHA1) {
        sha1_begin(&context.sha1);
        update = (void (*)(const void*, size_t, void*))sha1_hash;
        final = (void (*)(void*, void*))sha1_end;
        hash_len = 20;
    } else {
        bb_error_msg_and_die("algorithm not supported");
    }

    while (0 < (count = safe_read(src_fd, in_buf, 4096))) {
        update(in_buf, count, &context);
    }

    if (count == 0) {
        final(in_buf, &context);
        hash_value = hash_bin_to_hex(in_buf, hash_len);
    }

    RELEASE_CONFIG_BUFFER(in_buf);

    if (src_fd != STDIN_FILENO) {
        close(src_fd);
    }

    return hash_value;
}

int md5_sha1_sum_main(int argc, char **argv);
int md5_sha1_sum_main(int argc, char **argv)
{
    int return_value = EXIT_SUCCESS;
    uint8_t *hash_value;
    unsigned flags;
    hash_algo_t hash_algo = ENABLE_MD5SUM
        ? (ENABLE_SHA1SUM ? (applet_name[0] == 'm' ? HASH_MD5 : HASH_SHA1) : HASH_MD5)
        : HASH_SHA1;

    if (ENABLE_FEATURE_MD5_SHA1_SUM_CHECK)
        flags = getopt32(argv, "scw");
    else optind = 1;

    if (ENABLE_FEATURE_MD5_SHA1_SUM_CHECK && !(flags & FLAG_CHECK)) {
        if (flags & FLAG_SILENT) {
            bb_error_msg_and_die
                ("-%c is meaningful only when verifying checksums", 's');
        } else if (flags & FLAG_WARN) {
            bb_error_msg_and_die
                ("-%c is meaningful only when verifying checksums", 'w');
        }
    }

    if (argc == optind) {
        argv[argc++] = (char*)"-";
    }

    if (ENABLE_FEATURE_MD5_SHA1_SUM_CHECK && (flags & FLAG_CHECK)) {
        FILE *pre_computed_stream;
        int count_total = 0;
        int count_failed = 0;
        char *file_ptr = argv[optind];
        char *line;

        if (optind + 1 != argc) {
            bb_error_msg_and_die
                ("only one argument may be specified when using -c");
        }

        pre_computed_stream = stdin;
        if (NOT_LONE_DASH(file_ptr)) {
            pre_computed_stream = xfopen(file_ptr, "r");
        }

        while ((line = xmalloc_getline(pre_computed_stream)) != NULL) {
            char *filename_ptr;

            count_total++;
            filename_ptr = strstr(line, "  ");
            /* handle format for binary checksums */
            if (filename_ptr == NULL) {
                filename_ptr = strstr(line, " *");
            }
            if (filename_ptr == NULL) {
                if (flags & FLAG_WARN) {
                    bb_error_msg("invalid format");
                }
                count_failed++;
                return_value = EXIT_FAILURE;
                free(line);
                continue;
            }
            *filename_ptr = '\0';
            filename_ptr += 2;

            hash_value = hash_file(filename_ptr, hash_algo);

            if (hash_value && (strcmp((char*)hash_value, line) == 0)) {
                if (!(flags & FLAG_SILENT))
                    printf("%s: OK\n", filename_ptr);
            } else {
                if (!(flags & FLAG_SILENT))
                    printf("%s: FAILED\n", filename_ptr);
                count_failed++;
                return_value = EXIT_FAILURE;
            }
            /* possible free(NULL) */
            free(hash_value);
            free(line);
        }
        if (count_failed && !(flags & FLAG_SILENT)) {
            bb_error_msg("WARNING: %d of %d computed checksums did NOT match",
                         count_failed, count_total);
        }
        /*
        if (fclose_if_not_stdin(pre_computed_stream) == EOF) {
            bb_perror_msg_and_die("cannot close file %s", file_ptr);
        }
        */
    } else {
        while (optind < argc) {
            char *file_ptr = argv[optind++];

            hash_value = hash_file(file_ptr, hash_algo);
            if (hash_value == NULL) {
                return_value = EXIT_FAILURE;
            } else {
                printf("%s  %s\n", hash_value, file_ptr);
                free(hash_value);
            }
        }
    }
    return return_value;
}