cmd/bart/create.c

	create.c revision a272125655938e902d5c7d99d182d3b1e35f70eb
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <signal.h>
#include <unistd.h>
#include <sys/acl.h>
#include <sys/statvfs.h>
#include <sys/wait.h>
#include "bart.h"
#include <aclutils.h>

static int  sanitize_reloc_root(char *root, size_t bufsize);
static int  create_manifest_filelist(char **argv, char *reloc_root);
static int  create_manifest_rule(char *reloc_root, FILE *rule_fp);
static void output_manifest(void);
static int  eval_file(const char *fname, const struct stat64 *statb);
static char *sanitized_fname(const char *, boolean_t);
static char *get_acl_string(const char *fname, const struct stat64 *statb,
    int *err_code);
static int  generate_hash(int fdin, char *hash_str);
static int  read_filelist(char *reloc_root, char **argv, char *buf,
    size_t bufsize);
static int  walker(const char *name, const struct stat64 *sp,
    int type, struct FTW *ftwx);

/*
 * The following globals are necessary due to the "walker" function
 * provided by nftw().  Since there is no way to pass them through to the
 * walker function, they must be global.
 */
static int      compute_chksum = 1, eval_err = 0;
static struct rule  *subtree_root;
static char     reloc_root[PATH_MAX];
static struct statvfs64 parent_vfs;

int
bart_create(int argc, char **argv)
{
    boolean_t   filelist_input;
    int     ret, c, output_pipe[2];
    FILE        *rules_fd = NULL;
    pid_t       pid;

    filelist_input = B_FALSE;
    reloc_root[0] = '\0';

    while ((c = getopt(argc, argv, "Inr:R:")) != EOF) {
        switch (c) {
        case 'I':
            if (rules_fd != NULL) {
                (void) fprintf(stderr, "%s", INPUT_ERR);
                usage();
            }
            filelist_input = B_TRUE;
            break;

        case 'n':
            compute_chksum = 0;
            break;

        case 'r':
            if (strcmp(optarg, "-") == 0)
                rules_fd = stdin;
            else
                rules_fd = fopen(optarg, "r");
            if (rules_fd == NULL) {
                perror(optarg);
                usage();
            }
            break;

        case 'R':
            (void) strlcpy(reloc_root, optarg, sizeof (reloc_root));
            ret = sanitize_reloc_root(reloc_root,
                sizeof (reloc_root));
            if (ret == 0)
                usage();
            break;

        case '?':
        default :
            usage();
        }
    }
    argv += optind;

    if (pipe(output_pipe) < 0) {
        perror("");
        exit(FATAL_EXIT);
    }

    pid = fork();
    if (pid < 0) {
        perror(NULL);
        exit(FATAL_EXIT);
    }

    /*
     * Break the creation of a manifest into two parts: the parent process
     * generated the data whereas the child process sorts the data.
     *
     * The processes communicate through the pipe.
     */
    if (pid > 0) {
        /*
         * Redirect the stdout of this process so it goes into
         * output_pipe[0].  The output of this process will be read
         * by the child, which will sort the output.
         */
        if (dup2(output_pipe[0], STDOUT_FILENO) != STDOUT_FILENO) {
            perror(NULL);
            exit(FATAL_EXIT);
        }
        (void) close(output_pipe[0]);
        (void) close(output_pipe[1]);

        if (filelist_input == B_TRUE) {
            ret = create_manifest_filelist(argv, reloc_root);
        } else {
            ret = create_manifest_rule(reloc_root, rules_fd);
        }

        /* Close stdout so the sort in the child proc will complete */
        (void) fclose(stdout);
    } else {
        /*
         * Redirect the stdin of this process so its read in from
         * the pipe, which is the parent process in this case.
         */
        if (dup2(output_pipe[1], STDIN_FILENO) != STDIN_FILENO) {
            perror(NULL);
            exit(FATAL_EXIT);
        }
        (void) close(output_pipe[0]);

        output_manifest();
    }

    /* Wait for the child proc (the sort) to complete */
    (void) wait(0);

    return (ret);
}

/*
 * Handle the -R option and sets 'root' to be the absolute path of the
 * relocatable root.  This is useful when the user specifies '-R ../../foo'.
 *
 * Return code is whether or not the location spec'd by the -R flag is a
 * directory or not.
 */
static int
sanitize_reloc_root(char *root, size_t bufsize)
{
    char        pwd[PATH_MAX];

    /*
     * First, save the current directory and go to the location
     * specified with the -R option.
     */
    (void) getcwd(pwd, sizeof (pwd));
    if (chdir(root) < 0) {
        /* Failed to change directory, something is wrong.... */
        perror(root);
        return (0);
    }

    /*
     * Save the absolute path of the relocatable root directory.
     */
    (void) getcwd(root, bufsize);

    /*
     * Now, go back to where we started, necessary for picking up a rules
     * file.
     */
    if (chdir(pwd) < 0) {
        /* Failed to change directory, something is wrong.... */
        perror(root);
        return (0);
    }

    /*
     * Make sure the path returned does not have a trailing /. This
     * can only happen when the entire pathname is "/".
     */
    if (strcmp(root, "/") == 0)
        root[0] = '\0';

    /*
     * Since the earlier chdir() succeeded, return success.
     */
    return (1);
}

/*
 * This is the worker bee which creates the manifest based upon the command
 * line options supplied by the user.
 *
 * NOTE: create_manifest() eventually outputs data to a pipe, which is read in
 * by the child process.  The child process is running output_manifest(), which
 * is responsible for generating sorted output.
 */
static int
create_manifest_rule(char *reloc_root, FILE *rule_fp)
{
    struct rule *root;
    int     ret_status = EXIT;
    uint_t      flags;

    if (compute_chksum)
        flags = ATTR_CONTENTS;
    else
        flags = 0;
    ret_status = read_rules(rule_fp, reloc_root, flags, 1);

    /* Loop through every single subtree */
    for (root = get_first_subtree(); root != NULL;
        root = get_next_subtree(root)) {

        /*
         * Check to see if this subtree should have contents
         * checking turned on or off.
         *
         * NOTE: The 'compute_chksum' and 'parent_vfs'
         * are a necessary hack: the variables are used in
         * walker(), both directly and indirectly.  Since
         * the parameters to walker() are defined by nftw(),
         * the globals are really a backdoor mechanism.
         */
        ret_status = statvfs64(root->subtree, &parent_vfs);
        if (ret_status < 0) {
            perror(root->subtree);
            continue;
        }

        /*
         * Walk the subtree and invoke the callback function
         * walker()
         */
        subtree_root = root;
        (void) nftw64(root->subtree, &walker, 20, FTW_PHYS);

        /*
         * Ugly but necessary:
         *
         * walker() must return 0, or the tree walk will stop,
         * so warning flags must be set through a global.
         */
        if (eval_err == WARNING_EXIT)
            ret_status = WARNING_EXIT;

    }
    return (ret_status);
}

static int
create_manifest_filelist(char **argv, char *reloc_root)
{
    int ret_status = EXIT;
    char    input_fname[PATH_MAX];

    while (read_filelist(reloc_root, argv,
        input_fname, sizeof (input_fname)) != -1) {

        struct stat64   stat_buf;
        int     ret;

        ret = lstat64(input_fname, &stat_buf);
        if (ret < 0) {
            ret_status = WARNING_EXIT;
            perror(input_fname);
        } else {
            ret = eval_file(input_fname, &stat_buf);

            if (ret == WARNING_EXIT)
                ret_status = WARNING_EXIT;
        }
    }

    return (ret_status);
}

/*
 * output_manifest() the child process.  It reads in the output from
 * create_manifest() and sorts it.
 */
static void
output_manifest(void)
{
    char    *env[] = {"LC_CTYPE=C", "LC_COLLATE=C", "LC_NUMERIC=C", NULL};
    time_t      time_val;
    struct tm   *tm;
    char        time_buf[1024];

    (void) printf("%s", MANIFEST_VER);
    time_val = time((time_t)0);
    tm = localtime(&time_val);
    (void) strftime(time_buf, sizeof (time_buf), "%A, %B %d, %Y (%T)", tm);
    (void) printf("! %s\n", time_buf);
    (void) printf("%s", FORMAT_STR);
    (void) fflush(stdout);
    /*
     * Simply run sort and read from the the current stdin, which is really
     * the output of create_manifest().
     * Also, make sure the output is unique, since a given file may be
     * included by several stanzas.
     */
    if (execle("/usr/bin/sort", "sort", "-u", NULL, env) < 0) {
        perror("");
        exit(FATAL_EXIT);
    }

    /*NOTREACHED*/
}

/*
 * Callback function for nftw()
 */
static int
walker(const char *name, const struct stat64 *sp, int type, struct FTW *ftwx)
{
    int         ret;
    struct statvfs64    path_vfs;
    boolean_t       dir_flag = B_FALSE;
    struct rule     *rule;

    switch (type) {
    case FTW_F: /* file         */
        rule = check_rules(name, 'F');
        if (rule != NULL) {
            if (rule->attr_list & ATTR_CONTENTS)
                compute_chksum = 1;
            else
                compute_chksum = 0;
        }
        break;
    case FTW_SL:    /* symbolic link    */
    case FTW_DP:    /* end of directory */
    case FTW_DNR:   /* unreadable directory */
    case FTW_NS:    /* unstatable file  */
        break;
    case FTW_D: /* enter directory      */
        dir_flag = B_TRUE;
        ret = statvfs64(name, &path_vfs);
        if (ret < 0)
            eval_err = WARNING_EXIT;
        break;
    default:
        (void) fprintf(stderr, INVALID_FILE, name);
        eval_err = WARNING_EXIT;
        break;
    }

    /* This is the function which really processes the file */
    ret = eval_file(name, sp);

    /*
     * Since the parameters to walker() are constrained by nftw(),
     * need to use a global to reflect a WARNING.  Sigh.
     */
    if (ret == WARNING_EXIT)
        eval_err = WARNING_EXIT;

    /*
     * This is a case of a directory which crosses into a mounted
     * filesystem of a different type, e.g., UFS -> NFS.
     * BART should not walk the new filesystem (by specification), so
     * set this consolidation-private flag so the rest of the subtree
     * under this directory is not waled.
     */
    if (dir_flag &&
        (strcmp(parent_vfs.f_basetype, path_vfs.f_basetype) != 0))
        ftwx->quit = FTW_PRUNE;

    return (0);
}

/*
 * This file does the per-file evaluation and is run to generate every entry
 * in the manifest.
 *
 * All output is written to a pipe which is read by the child process,
 * which is running output_manifest().
 */
static int
eval_file(const char *fname, const struct stat64 *statb)
{
    int fd, ret, err_code, i;
    char    last_field[PATH_MAX], ftype, *acl_str;
    char    *quoted_name;

    err_code = EXIT;

    switch (statb->st_mode & S_IFMT) {
    /* Regular file */
    case S_IFREG: ftype = 'F'; break;

    /* Directory */
    case S_IFDIR: ftype = 'D'; break;

    /* Block Device */
    case S_IFBLK: ftype = 'B'; break;

    /* Character Device */
    case S_IFCHR: ftype = 'C'; break;

    /* Named Pipe */
    case S_IFIFO: ftype = 'P'; break;

    /* Socket */
    case S_IFSOCK: ftype = 'S'; break;

    /* Door */
    case S_IFDOOR: ftype = 'O'; break;

    /* Symbolic link */
    case S_IFLNK: ftype = 'L'; break;

    default: ftype = '-'; break;
    }

    /* First, make sure this file should be cataloged */

    if ((subtree_root != NULL) &&
        (exclude_fname(fname, ftype, subtree_root)))
        return (err_code);

    for (i = 0; i < PATH_MAX; i++)
        last_field[i] = '\0';

    /*
     * Regular files, compute the MD5 checksum and put it into 'last_field'
     * UNLESS instructed to ignore the checksums.
     */
    if (ftype == 'F') {
        if (compute_chksum) {
            fd = open(fname, O_RDONLY|O_LARGEFILE);
            if (fd < 0) {
                err_code = WARNING_EXIT;
                perror(fname);

                /* default value since the computution failed */
                (void) strcpy(last_field, "-");
            } else {
                if (generate_hash(fd, last_field) != 0) {
                    err_code = WARNING_EXIT;
                    (void) fprintf(stderr, CONTENTS_WARN,
                        fname);
                    (void) strcpy(last_field, "-");
                }
            }
            (void) close(fd);
        }
        /* Instructed to ignore checksums, just put in a '-' */
        else
            (void) strcpy(last_field, "-");
    }

    /*
     * For symbolic links, put the destination of the symbolic link into
     * 'last_field'
     */
    if (ftype == 'L') {
        ret = readlink(fname, last_field, sizeof (last_field));
        if (ret < 0) {
            err_code = WARNING_EXIT;
            perror(fname);

            /* default value since the computation failed */
            (void) strcpy(last_field, "-");
        }
        else
            (void) strlcpy(last_field,
                sanitized_fname(last_field, B_FALSE),
                sizeof (last_field));

        /*
         * Boundary condition: possible for a symlink to point to
         * nothing [ ln -s '' link_name ].  For this case, set the
         * destination to "\000".
         */
        if (strlen(last_field) == 0)
            (void) strcpy(last_field, "\\000");
    }

    acl_str = get_acl_string(fname, statb, &err_code);

    /* Sanitize 'fname', so its in the proper format for the manifest */
    quoted_name = sanitized_fname(fname, B_TRUE);

    /* Start to build the entry.... */
    (void) printf("%s %c %d %o %s %x %d %d", quoted_name, ftype,
        (int)statb->st_size, (int)statb->st_mode, acl_str,
        (int)statb->st_mtime, (int)statb->st_uid, (int)statb->st_gid);

    /* Finish it off based upon whether or not it's a device node */
    if ((ftype == 'B') || (ftype == 'C'))
        (void) printf(" %x\n", (int)statb->st_rdev);
    else if (strlen(last_field) > 0)
        (void) printf(" %s\n", last_field);
    else
        (void) printf("\n");

    /* free the memory consumed */
    free(acl_str);
    free(quoted_name);

    return (err_code);
}

/*
 * When creating a manifest, make sure all '?', tabs, space, newline, '/'
 * and '[' are all properly quoted.  Convert them to a "\ooo" where the 'ooo'
 * represents their octal value. For filesystem objects, as opposed to symlink
 * targets, also canonicalize the pathname.
 */
static char *
sanitized_fname(const char *fname, boolean_t canon_path)
{
    const char *ip;
    unsigned char ch;
    char *op, *quoted_name;

    /* Initialize everything */
    quoted_name = safe_calloc((4 * PATH_MAX) + 1);
    ip = fname;
    op = quoted_name;

    if (canon_path) {
        /*
         * In the case when a relocatable root was used, the relocatable
         * root should *not* be part of the manifest.
         */
        ip += strlen(reloc_root);

        /*
         * In the case when the '-I' option was used, make sure
         * the quoted_name starts with a '/'.
         */
        if (*ip != '/')
            *op++ = '/';
    }

    /* Now walk through 'fname' and build the quoted string */
    while ((ch = *ip++) != 0) {
        switch (ch) {
        /* Quote the following characters */
        case ' ':
        case '*':
        case '\n':
        case '?':
        case '[':
        case '\\':
        case '\t':
            op += sprintf(op, "\\%.3o", (unsigned char)ch);
            break;

        /* Otherwise, simply append them */
        default:
            *op++ = ch;
            break;
        }
    }

    *op = 0;

    return (quoted_name);
}

/*
 * Function responsible for generating the ACL information for a given
 * file.  Note, the string is put into buffer malloc'd by this function.
 * It's the responsibility of the caller to free the buffer.  This function
 * should never return a NULL pointer.
 */
static char *
get_acl_string(const char *fname, const struct stat64 *statb, int *err_code)
{
    acl_t       *aclp;
    char        *acltext;
    int     error;

    if (S_ISLNK(statb->st_mode)) {
        return (safe_strdup("-"));
    }

    /*
     *  Include trivial acl's
     */
    error = acl_get(fname, 0, &aclp);

    if (error != 0) {
        *err_code = WARNING_EXIT;
        (void) fprintf(stderr, "%s: %s\n", fname, acl_strerror(error));
        return (safe_strdup("-"));
    } else {
        acltext = acl_totext(aclp, 0);
        acl_free(aclp);
        if (acltext == NULL)
            return (safe_strdup("-"));
        else
            return (acltext);
    }
}


/*
 *
 * description: This routine reads stdin in BUF_SIZE chunks, uses the bits
 *      to update the md5 hash buffer, and outputs the chunks
 *      to stdout.  When stdin is exhausted, the hash is computed,
 *      converted to a hexadecimal string, and returned.
 *
 * returns: The md5 hash of stdin, or NULL if unsuccessful for any reason.
 */
static int
generate_hash(int fdin, char *hash_str)
{
    unsigned char buf[BUF_SIZE];
    unsigned char hash[MD5_DIGEST_LENGTH];
    int i, amtread;
    MD5_CTX ctx;

    MD5Init(&ctx);

    for (;;) {
        amtread = read(fdin, buf, sizeof (buf));
        if (amtread == 0)
            break;
        if (amtread <  0)
            return (1);

        /* got some data.  Now update hash */
        MD5Update(&ctx, buf, amtread);
    }

    /* done passing through data, calculate hash */
    MD5Final(hash, &ctx);

    for (i = 0; i < MD5_DIGEST_LENGTH; i++)
        (void) sprintf(hash_str + (i*2), "%2.2x", hash[i]);

    return (0);
}

/*
 * Used by 'bart create' with the '-I' option.  Return each entry into a 'buf'
 * with the appropriate exit code: '0' for success and '-1' for failure.
 */
static int
read_filelist(char *reloc_root, char **argv, char *buf, size_t bufsize)
{
    static int      argv_index = -1;
    static boolean_t    read_stdinput = B_FALSE;
    char            temp_buf[PATH_MAX];
    char            *cp;

    /*
     * INITIALIZATION:
     * Setup this code so it knows whether or not to read sdtin.
     * Also, if reading from argv, setup the index, "argv_index"
     */
    if (argv_index == -1) {
        argv_index = 0;

        /* In this case, no args after '-I', so read stdin */
        if (argv[0] == NULL)
            read_stdinput = B_TRUE;
    }

    buf[0] = '\0';

    if (read_stdinput) {
        if (fgets(temp_buf, PATH_MAX, stdin) == NULL)
            return (-1);
        cp = strtok(temp_buf, "\n");
    } else {
        cp = argv[argv_index++];
    }

    if (cp == NULL)
        return (-1);

    /*
     * Unlike similar code elsewhere, avoid adding a leading
     * slash for relative pathnames.
     */
    (void) snprintf(buf, bufsize,
        (reloc_root[0] == '\0' || cp[0] == '/') ? "%s%s" : "%s/%s",
        reloc_root, cp);

    return (0);
}