/*      $NetBSD: ldconfig.c,v 1.48 2011/01/04 23:34:06 wiz Exp $        */

/*-
 * Copyright (c) 1998 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Paul Kranenburg.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
#include <sys/cdefs.h>

#ifndef lint
__RCSID("$NetBSD: ldconfig.c,v 1.48 2011/01/04 23:34:06 wiz Exp $");
#endif


#include <sys/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <sys/time.h>
#include <sys/mman.h>
#include <sys/exec_aout.h>
#include <a.out.h>
#include <ctype.h>
#include <dirent.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <link_aout.h>
#include <paths.h>

#include "shlib.h"

#define _PATH_LD_SO_CONF "/etc/ld.so.conf"

#undef major
#undef minor

static int                      verbose;
static int                      nostd;
static int                      noconf;
static int                      justread;
static int                      merge;

struct shlib_list {
        /* Internal list of shared libraries found */
        char                    *name;
        char                    *path;
        int                     dewey[MAXDEWEY];
        int                     ndewey;
#define major dewey[0]
#define minor dewey[1]
        struct shlib_list       *next;
};

static struct shlib_list        *shlib_head = NULL, **shlib_tail = &shlib_head;
static char                     *dir_list;

static void     enter(char *, char *, char *, int *, int);
static int      dodir(char *, int, int);
static int      do_conf(void);
static int      buildhints(void);
static int      readhints(void);
static void     listhints(void);
static int      hinthash(char *, int, int);

int
main(int argc, char *argv[])
{
        int     i, c;
        int     rval = 0;

        while ((c = getopt(argc, argv, "cmrsSv")) != -1) {
                switch (c) {
                case 'c':
                        noconf = 1;
                        break;
                case 'm':
                        merge = 1;
                        break;
                case 'r':
                        justread = 1;
                        break;
                case 's':
                        nostd = 1;
                        noconf = 1;
                        break;
                case 'S':
                        nostd = 1;
                        break;
                case 'v':
                        verbose = 1;
                        break;
                default:
                        errx(1, "usage: %s [-c][-m][-r][-s][-S][-v][dir ...]",
                                getprogname());
                        break;
                }
        }

        dir_list = xmalloc(1);
        *dir_list = '\0';

        if (justread || merge) {
                if ((rval = readhints()) != 0)
                        return (rval);
                if (justread) {
                        listhints();
                        return (rval);
                }
        }

        if (!nostd && !merge)
                std_search_path();

        for (i = 0; i < n_search_dirs; i++)
                rval |= dodir(search_dirs[i], 1, 0);

        if (!noconf && !merge)
                rval |= do_conf();

        for (i = optind; i < argc; i++) {
                rval |= dodir(argv[i], 0, 1);
        }

        rval |= buildhints();

        return (rval);
}

int
do_conf(void)
{
        FILE            *conf;
        char            *line, *c;
        char            *cline = NULL;
        size_t          len;
        int             rval = 0;
#ifdef __ELF__
        char            *aout_conf;

        aout_conf = xmalloc(sizeof(_PATH_EMUL_AOUT) +
            strlen(_PATH_LD_SO_CONF));
        strcpy(aout_conf, _PATH_EMUL_AOUT);
        strcat(aout_conf, _PATH_LD_SO_CONF);
        if ((conf = fopen(aout_conf, "r")) == NULL) {
                if (verbose)
                        warnx("can't open `%s'", aout_conf);
                free(aout_conf);
                return (0);
        }
        free(aout_conf);
#else
        if ((conf = fopen(_PATH_LD_SO_CONF, "r")) == NULL) {
                if (verbose) {
                        warnx("can't open `%s'", _PATH_LD_SO_CONF);
                }
                return (0);
        }
#endif

        while ((line = fgetln(conf, &len)) != NULL) {
                if (*line != '/')
                        continue;

                if (line[len-1] == '\n') {
                        line[--len] = '\0';
                } else {
                        cline = xmalloc(len+1);
                        memcpy(cline, line, len);
                        line = cline;
                        line[len] = '\0';
                }

                while (isblank((unsigned char)*line)) { line++; len--; }
                if ((c = strchr(line, '#')) == NULL)
                        c = line + len;
                while (--c >= line && isblank((unsigned char)*c)) continue;
                if (c >= line) {
                        *++c = '\0';
                        rval |= dodir(line, 0, 1);
                }

                if (cline) {
                        free(cline);
                        cline = NULL;
                }
        }

        (void) fclose(conf);

        return (rval);
}

int
dodir(char *dir, int silent, int update_dir_list)
{
        DIR             *dd;
        struct dirent   *dp;
        char            name[MAXPATHLEN];
        int             dewey[MAXDEWEY], ndewey;

        if ((dd = opendir(dir)) == NULL) {
                /* /emul/aout directories are allowed to not exist.
                 */
                if (!strncmp(dir, _PATH_EMUL_AOUT, sizeof(_PATH_EMUL_AOUT)-1))
                        return 0;
                if (!silent || errno != ENOENT)
                        warn("%s", dir);
                return (-1);
        }

        if (update_dir_list) {
                /* Check for duplicates? */
                char *cp = concat(dir_list, *dir_list?":":"", dir);
                free(dir_list);
                dir_list = cp;
        }

        while ((dp = readdir(dd)) != NULL) {
                int n;
                char *cp, *path;
                FILE *fp;
                struct exec ex;

                /* Check for `lib' prefix */
                if (dp->d_name[0] != 'l' ||
                    dp->d_name[1] != 'i' ||
                    dp->d_name[2] != 'b')
                        continue;

                /* Copy the entry minus prefix */
                (void)strcpy(name, dp->d_name + 3);
                n = strlen(name);
                if (n < 4)
                        continue;

                /* Find ".so." in name */
                for (cp = name + n - 4; cp > name; --cp) {
                        if (cp[0] == '.' &&
                            cp[1] == 's' &&
                            cp[2] == 'o' &&
                            cp[3] == '.')
                                break;
                }
                if (cp <= name)
                        continue;

                path = concat(dir, "/", dp->d_name);
                fp = fopen(path, "r");
                free(path);
                if (fp == NULL)
                        continue;
                n = fread(&ex, 1, sizeof(ex), fp);
                fclose(fp);
                if (n != sizeof(ex)
                    || N_GETMAGIC(ex) != ZMAGIC
                    || (N_GETFLAG(ex) & EX_DYNAMIC) == 0)
                        continue;

                *cp = '\0';
                if (!isdigit((unsigned char)*(cp+4)))
                        continue;

                memset(dewey, 0, sizeof(dewey));
                ndewey = getdewey(dewey, cp + 4);
                enter(dir, dp->d_name, name, dewey, ndewey);
        }

        (void) closedir(dd);

        return (0);
}

static void
enter(char *dir, char *file, char *name, int dewey[], int ndewey)
{
        struct shlib_list       *shp;

        for (shp = shlib_head; shp; shp = shp->next) {
                if (strcmp(name, shp->name) != 0 || major != shp->major)
                        continue;

                /* Name matches existing entry */
                if (cmpndewey(dewey, ndewey, shp->dewey, shp->ndewey) > 0) {

                        /* Update this entry with higher versioned lib */
                        if (verbose)
                                printf("Updating lib%s.%d.%d to %s/%s\n",
                                        shp->name, shp->major, shp->minor,
                                        dir, file);

                        free(shp->name);
                        shp->name = strdup(name);
                        free(shp->path);
                        shp->path = concat(dir, "/", file);
                        memcpy(shp->dewey, dewey, sizeof(shp->dewey));
                        shp->ndewey = ndewey;
                }
                break;
        }

        if (shp)
                /* Name exists: older version or just updated */
                return;

        /* Allocate new list element */
        if (verbose)
                printf("Adding %s/%s\n", dir, file);

        shp = (struct shlib_list *)xmalloc(sizeof *shp);
        shp->name = strdup(name);
        shp->path = concat(dir, "/", file);
        memcpy(shp->dewey, dewey, sizeof(shp->dewey));
        shp->ndewey = ndewey;
        shp->next = NULL;

        *shlib_tail = shp;
        shlib_tail = &shp->next;
}


#if DEBUG
/* test */
#undef _PATH_LD_HINTS
#define _PATH_LD_HINTS          "./ld.so.hints"
#endif

/* XXX - should be a common function with rtld.c */
int
hinthash(char *cp, int vmajor, int vminor)
{
        int     k = 0;

        while (*cp)
                k = (((k << 1) + (k >> 14)) ^ (*cp++)) & 0x3fff;

        k = (((k << 1) + (k >> 14)) ^ (vmajor*257)) & 0x3fff;
#if 0
        k = (((k << 1) + (k >> 14)) ^ (vminor*167)) & 0x3fff;
#endif

        return (k);
}

int
buildhints(void)
{
        struct hints_header     hdr;
        struct hints_bucket     *blist;
        struct shlib_list       *shp;
        char                    *strtab;
        int                     i, n, str_index = 0;
        int                     strtab_sz = 0;  /* Total length of strings */
        int                     nhints = 0;     /* Total number of hints */
        int                     fd;
        char                    *tempfile;

        for (shp = shlib_head; shp; shp = shp->next) {
                strtab_sz += 1 + strlen(shp->name);
                strtab_sz += 1 + strlen(shp->path);
                nhints++;
        }

        /* Fill hints file header */
        hdr.hh_magic = HH_MAGIC;
        hdr.hh_version = LD_HINTS_VERSION_2;
        hdr.hh_nbucket = 1 * nhints;
        n = hdr.hh_nbucket * sizeof(struct hints_bucket);
        hdr.hh_hashtab = sizeof(struct hints_header);
        hdr.hh_strtab = hdr.hh_hashtab + n;
        hdr.hh_dirlist = strtab_sz;
        strtab_sz += 1 + strlen(dir_list);
        hdr.hh_strtab_sz = strtab_sz;
        hdr.hh_ehints = hdr.hh_strtab + hdr.hh_strtab_sz;

        if (verbose)
                printf("Totals: entries %d, buckets %ld, string size %d\n",
                                        nhints, hdr.hh_nbucket, strtab_sz);

        /* Allocate buckets and string table */
        blist = (struct hints_bucket *)xmalloc(n);
        memset(blist, 0, n);
        for (i = 0; i < hdr.hh_nbucket; i++)
                /* Empty all buckets */
                blist[i].hi_next = -1;

        strtab = (char *)xmalloc(strtab_sz);

        /* Enter all */
        for (shp = shlib_head; shp; shp = shp->next) {
                struct hints_bucket     *bp;

                bp = blist +
                  (hinthash(shp->name, shp->major, shp->minor) % hdr.hh_nbucket);

                if (bp->hi_pathx) {
                        for (i = 0; i < hdr.hh_nbucket; i++) {
                                if (blist[i].hi_pathx == 0)
                                        break;
                        }
                        if (i == hdr.hh_nbucket) {
                                warnx("Bummer!");
                                goto out;
                        }
                        while (bp->hi_next != -1)
                                bp = &blist[bp->hi_next];
                        bp->hi_next = i;
                        bp = blist + i;
                }

                /* Insert strings in string table */
                bp->hi_namex = str_index;
                strcpy(strtab + str_index, shp->name);
                str_index += 1 + strlen(shp->name);

                bp->hi_pathx = str_index;
                strcpy(strtab + str_index, shp->path);
                str_index += 1 + strlen(shp->path);

                /* Copy versions */
                memcpy(bp->hi_dewey, shp->dewey, sizeof(bp->hi_dewey));
                bp->hi_ndewey = shp->ndewey;
        }

        /* Copy search directories */
        strcpy(strtab + str_index, dir_list);
        str_index += 1 + strlen(dir_list);

        /* Sanity check */
        if (str_index != strtab_sz) {
                errx(1, "str_index(%d) != strtab_sz(%d)", str_index, strtab_sz);
        }

        tempfile = concat(_PATH_LD_HINTS, ".XXXXXX", "");
        if ((fd = mkstemp(tempfile)) == -1) {
                warn("%s", tempfile);
                goto out;
        }

        if (write(fd, &hdr, sizeof(struct hints_header)) !=
            sizeof(struct hints_header)) {
                warn("%s", _PATH_LD_HINTS);
                goto fdout;
        }
        if ((size_t)write(fd, blist, hdr.hh_nbucket * sizeof(struct hints_bucket)) !=
                  hdr.hh_nbucket * sizeof(struct hints_bucket)) {
                warn("%s", _PATH_LD_HINTS);
                goto fdout;
        }
        if (write(fd, strtab, strtab_sz) != strtab_sz) {
                warn("%s", _PATH_LD_HINTS);
                goto fdout;
        }
        if (fchmod(fd, 0444) == -1) {
                warn("%s", _PATH_LD_HINTS);
                goto fdout;
        }
        if (close(fd) != 0) {
                warn("%s", _PATH_LD_HINTS);
                goto out;
        }

        /* Install it */
        if (unlink(_PATH_LD_HINTS) != 0 && errno != ENOENT) {
                warn("%s", _PATH_LD_HINTS);
                goto out;
        }

        if (rename(tempfile, _PATH_LD_HINTS) != 0) {
                warn("%s", _PATH_LD_HINTS);
                goto out;
        }

        free(blist);
        free(strtab);
        return 0;
fdout:
        (void)close(fd);
out:
        free(blist);
        free(strtab);
        return -1;
}

static int
readhints(void)
{
        int                     fd;
        void                    *addr = (void *) -1;
        size_t                  msize = 0;
        struct hints_header     *hdr;
        struct hints_bucket     *blist;
        char                    *strtab;
        struct shlib_list       *shp;
        int                     i;
        struct                  stat st;
        int                     error = 0;

        if ((fd = open(_PATH_LD_HINTS, O_RDONLY, 0)) == -1) {
                warn("%s", _PATH_LD_HINTS);
                goto cleanup;
        }

        if (fstat(fd, &st) == -1) {
                warn("%s", _PATH_LD_HINTS);
                goto cleanup;
        }

        msize = (size_t)st.st_size;
        if (msize < sizeof(*hdr)) {
                warnx("%s: File too short", _PATH_LD_HINTS);
                goto cleanup;
        }

        addr = mmap(0, msize, PROT_READ, MAP_FILE|MAP_PRIVATE, fd, 0);

        if (addr == (void *)-1) {
                warn("%s", _PATH_LD_HINTS);
                goto cleanup;
        }

        hdr = (struct hints_header *)addr;
        if (HH_BADMAG(*hdr)) {
                warnx("%s: Bad magic: %lo",
                    _PATH_LD_HINTS, hdr->hh_magic);
                goto cleanup;
        }

        if (hdr->hh_version != LD_HINTS_VERSION_2) {
                warnx("Unsupported version: %ld", hdr->hh_version);
                goto cleanup;
        }


        blist = (struct hints_bucket *)((char *)addr + hdr->hh_hashtab);
        strtab = ((char *)addr + hdr->hh_strtab);

        for (i = 0; i < hdr->hh_nbucket; i++) {
                struct hints_bucket     *bp = &blist[i];

                /* Sanity check */
                if (bp->hi_namex >= hdr->hh_strtab_sz) {
                        warnx("Bad name index: %#x", bp->hi_namex);
                        goto cleanup;
                }
                if (bp->hi_pathx >= hdr->hh_strtab_sz) {
                        warnx("Bad path index: %#x", bp->hi_pathx);
                        goto cleanup;
                }

                /* Allocate new list element */
                shp = (struct shlib_list *)xmalloc(sizeof *shp);
                shp->name = strdup(strtab + bp->hi_namex);
                shp->path = strdup(strtab + bp->hi_pathx);
                memcpy(shp->dewey, bp->hi_dewey, sizeof(shp->dewey));
                shp->ndewey = bp->hi_ndewey;
                shp->next = NULL;

                *shlib_tail = shp;
                shlib_tail = &shp->next;
        }
        dir_list = strdup(strtab + hdr->hh_dirlist);
        goto done;
cleanup:
        error = 1;
done:
        if (fd != -1)
                close(fd);
        if (addr != (void *)-1)
                munmap(addr, msize);
        return error;

}

static void
listhints(void)
{
        struct shlib_list       *shp;
        int                     i;

        printf("%s:\n", _PATH_LD_HINTS);
        printf("\tsearch directories: %s\n", dir_list);

        for (i = 0, shp = shlib_head; shp; i++, shp = shp->next)
                printf("\t%d:-l%s.%d.%d => %s\n",
                        i, shp->name, shp->major, shp->minor, shp->path);

        return;
}