1/*
2 * Copyright 2015-2023 The OpenSSL Project Authors. All Rights Reserved.
3 * Copyright (c) 2013-2014 Timo Ter��s <timo.teras@gmail.com>
4 *
5 * Licensed under the Apache License 2.0 (the "License").  You may not use
6 * this file except in compliance with the License.  You can obtain a copy
7 * in the file LICENSE in the source distribution or at
8 * https://www.openssl.org/source/license.html
9 */
10
11#include "apps.h"
12#include "progs.h"
13
14#if defined(OPENSSL_SYS_UNIX) || defined(__APPLE__) || \
15    (defined(__VMS) && defined(__DECC) && __CRTL_VER >= 80300000)
16# include <unistd.h>
17# include <stdio.h>
18# include <limits.h>
19# include <errno.h>
20# include <string.h>
21# include <ctype.h>
22# include <sys/stat.h>
23
24/*
25 * Make sure that the processing of symbol names is treated the same as when
26 * libcrypto is built.  This is done automatically for public headers (see
27 * include/openssl/__DECC_INCLUDE_PROLOGUE.H and __DECC_INCLUDE_EPILOGUE.H),
28 * but not for internal headers.
29 */
30# ifdef __VMS
31#  pragma names save
32#  pragma names as_is,shortened
33# endif
34
35# include "internal/o_dir.h"
36
37# ifdef __VMS
38#  pragma names restore
39# endif
40
41# include <openssl/evp.h>
42# include <openssl/pem.h>
43# include <openssl/x509.h>
44
45# ifndef PATH_MAX
46#  define PATH_MAX 4096
47# endif
48# define MAX_COLLISIONS  256
49
50# if defined(OPENSSL_SYS_VXWORKS)
51/*
52 * VxWorks has no symbolic links
53 */
54
55#  define lstat(path, buf) stat(path, buf)
56
57int symlink(const char *target, const char *linkpath)
58{
59    errno = ENOSYS;
60    return -1;
61}
62
63ssize_t readlink(const char *pathname, char *buf, size_t bufsiz)
64{
65    errno = ENOSYS;
66    return -1;
67}
68# endif
69
70typedef struct hentry_st {
71    struct hentry_st *next;
72    char *filename;
73    unsigned short old_id;
74    unsigned char need_symlink;
75    unsigned char digest[EVP_MAX_MD_SIZE];
76} HENTRY;
77
78typedef struct bucket_st {
79    struct bucket_st *next;
80    HENTRY *first_entry, *last_entry;
81    unsigned int hash;
82    unsigned short type;
83    unsigned short num_needed;
84} BUCKET;
85
86enum Type {
87    /* Keep in sync with |suffixes|, below. */
88    TYPE_CERT=0, TYPE_CRL=1
89};
90
91enum Hash {
92    HASH_OLD, HASH_NEW, HASH_BOTH
93};
94
95
96static int evpmdsize;
97static const EVP_MD *evpmd;
98static int remove_links = 1;
99static int verbose = 0;
100static BUCKET *hash_table[257];
101
102static const char *suffixes[] = { "", "r" };
103static const char *extensions[] = { "pem", "crt", "cer", "crl" };
104
105
106static void bit_set(unsigned char *set, unsigned int bit)
107{
108    set[bit >> 3] |= 1 << (bit & 0x7);
109}
110
111static int bit_isset(unsigned char *set, unsigned int bit)
112{
113    return set[bit >> 3] & (1 << (bit & 0x7));
114}
115
116
117/*
118 * Process an entry; return number of errors.
119 */
120static int add_entry(enum Type type, unsigned int hash, const char *filename,
121                      const unsigned char *digest, int need_symlink,
122                      unsigned short old_id)
123{
124    static BUCKET nilbucket;
125    static HENTRY nilhentry;
126    BUCKET *bp;
127    HENTRY *ep, *found = NULL;
128    unsigned int ndx = (type + hash) % OSSL_NELEM(hash_table);
129
130    for (bp = hash_table[ndx]; bp; bp = bp->next)
131        if (bp->type == type && bp->hash == hash)
132            break;
133    if (bp == NULL) {
134        bp = app_malloc(sizeof(*bp), "hash bucket");
135        *bp = nilbucket;
136        bp->next = hash_table[ndx];
137        bp->type = type;
138        bp->hash = hash;
139        hash_table[ndx] = bp;
140    }
141
142    for (ep = bp->first_entry; ep; ep = ep->next) {
143        if (digest && memcmp(digest, ep->digest, evpmdsize) == 0) {
144            BIO_printf(bio_err,
145                       "%s: warning: skipping duplicate %s in %s\n",
146                       opt_getprog(),
147                       type == TYPE_CERT ? "certificate" : "CRL", filename);
148            return 0;
149        }
150        if (strcmp(filename, ep->filename) == 0) {
151            found = ep;
152            if (digest == NULL)
153                break;
154        }
155    }
156    ep = found;
157    if (ep == NULL) {
158        if (bp->num_needed >= MAX_COLLISIONS) {
159            BIO_printf(bio_err,
160                       "%s: error: hash table overflow for %s\n",
161                       opt_getprog(), filename);
162            return 1;
163        }
164        ep = app_malloc(sizeof(*ep), "collision bucket");
165        *ep = nilhentry;
166        ep->old_id = ~0;
167        ep->filename = OPENSSL_strdup(filename);
168        if (ep->filename == NULL) {
169            OPENSSL_free(ep);
170            ep = NULL;
171            BIO_printf(bio_err, "out of memory\n");
172            return 1;
173        }
174        if (bp->last_entry)
175            bp->last_entry->next = ep;
176        if (bp->first_entry == NULL)
177            bp->first_entry = ep;
178        bp->last_entry = ep;
179    }
180
181    if (old_id < ep->old_id)
182        ep->old_id = old_id;
183    if (need_symlink && !ep->need_symlink) {
184        ep->need_symlink = 1;
185        bp->num_needed++;
186        memcpy(ep->digest, digest, evpmdsize);
187    }
188    return 0;
189}
190
191/*
192 * Check if a symlink goes to the right spot; return 0 if okay.
193 * This can be -1 if bad filename, or an error count.
194 */
195static int handle_symlink(const char *filename, const char *fullpath)
196{
197    unsigned int hash = 0;
198    int i, type, id;
199    unsigned char ch;
200    char linktarget[PATH_MAX], *endptr;
201    ossl_ssize_t n;
202
203    for (i = 0; i < 8; i++) {
204        ch = filename[i];
205        if (!isxdigit(ch))
206            return -1;
207        hash <<= 4;
208        hash += OPENSSL_hexchar2int(ch);
209    }
210    if (filename[i++] != '.')
211        return -1;
212    for (type = OSSL_NELEM(suffixes) - 1; type > 0; type--) {
213        const char *suffix = suffixes[type];
214        if (OPENSSL_strncasecmp(suffix, &filename[i], strlen(suffix)) == 0)
215            break;
216    }
217    i += strlen(suffixes[type]);
218
219    id = strtoul(&filename[i], &endptr, 10);
220    if (*endptr != '\0')
221        return -1;
222
223    n = readlink(fullpath, linktarget, sizeof(linktarget));
224    if (n < 0 || n >= (int)sizeof(linktarget))
225        return -1;
226    linktarget[n] = 0;
227
228    return add_entry(type, hash, linktarget, NULL, 0, id);
229}
230
231/*
232 * process a file, return number of errors.
233 */
234static int do_file(const char *filename, const char *fullpath, enum Hash h)
235{
236    STACK_OF (X509_INFO) *inf = NULL;
237    X509_INFO *x;
238    const X509_NAME *name = NULL;
239    BIO *b;
240    const char *ext;
241    unsigned char digest[EVP_MAX_MD_SIZE];
242    int type, errs = 0;
243    size_t i;
244
245    /* Does it end with a recognized extension? */
246    if ((ext = strrchr(filename, '.')) == NULL)
247        goto end;
248    for (i = 0; i < OSSL_NELEM(extensions); i++) {
249        if (OPENSSL_strcasecmp(extensions[i], ext + 1) == 0)
250            break;
251    }
252    if (i >= OSSL_NELEM(extensions))
253        goto end;
254
255    /* Does it have X.509 data in it? */
256    if ((b = BIO_new_file(fullpath, "r")) == NULL) {
257        BIO_printf(bio_err, "%s: error: skipping %s, cannot open file\n",
258                   opt_getprog(), filename);
259        errs++;
260        goto end;
261    }
262    inf = PEM_X509_INFO_read_bio(b, NULL, NULL, NULL);
263    BIO_free(b);
264    if (inf == NULL)
265        goto end;
266
267    if (sk_X509_INFO_num(inf) != 1) {
268        BIO_printf(bio_err,
269                   "%s: warning: skipping %s,"
270                   "it does not contain exactly one certificate or CRL\n",
271                   opt_getprog(), filename);
272        /* This is not an error. */
273        goto end;
274    }
275    x = sk_X509_INFO_value(inf, 0);
276    if (x->x509 != NULL) {
277        type = TYPE_CERT;
278        name = X509_get_subject_name(x->x509);
279        if (!X509_digest(x->x509, evpmd, digest, NULL)) {
280            BIO_printf(bio_err, "out of memory\n");
281            ++errs;
282            goto end;
283        }
284    } else if (x->crl != NULL) {
285        type = TYPE_CRL;
286        name = X509_CRL_get_issuer(x->crl);
287        if (!X509_CRL_digest(x->crl, evpmd, digest, NULL)) {
288            BIO_printf(bio_err, "out of memory\n");
289            ++errs;
290            goto end;
291        }
292    } else {
293        ++errs;
294        goto end;
295    }
296    if (name != NULL) {
297        if (h == HASH_NEW || h == HASH_BOTH) {
298            int ok;
299            unsigned long hash_value =
300                X509_NAME_hash_ex(name,
301                                  app_get0_libctx(), app_get0_propq(), &ok);
302
303            if (ok) {
304                errs += add_entry(type, hash_value, filename, digest, 1, ~0);
305            } else {
306                BIO_printf(bio_err, "%s: error calculating SHA1 hash value\n",
307                           opt_getprog());
308                errs++;
309            }
310        }
311        if ((h == HASH_OLD) || (h == HASH_BOTH))
312            errs += add_entry(type, X509_NAME_hash_old(name),
313                              filename, digest, 1, ~0);
314    }
315
316end:
317    sk_X509_INFO_pop_free(inf, X509_INFO_free);
318    return errs;
319}
320
321static void str_free(char *s)
322{
323    OPENSSL_free(s);
324}
325
326static int ends_with_dirsep(const char *path)
327{
328    if (*path != '\0')
329        path += strlen(path) - 1;
330# if defined __VMS
331    if (*path == ']' || *path == '>' || *path == ':')
332        return 1;
333# elif defined _WIN32
334    if (*path == '\\')
335        return 1;
336# endif
337    return *path == '/';
338}
339
340static int sk_strcmp(const char * const *a, const char * const *b)
341{
342    return strcmp(*a, *b);
343}
344
345/*
346 * Process a directory; return number of errors found.
347 */
348static int do_dir(const char *dirname, enum Hash h)
349{
350    BUCKET *bp, *nextbp;
351    HENTRY *ep, *nextep;
352    OPENSSL_DIR_CTX *d = NULL;
353    struct stat st;
354    unsigned char idmask[MAX_COLLISIONS / 8];
355    int n, numfiles, nextid, dirlen, buflen, errs = 0;
356    size_t i, fname_max_len = 20; /* maximum length of "%08x.r%d" */
357    const char *pathsep = "";
358    const char *filename;
359    char *buf = NULL, *copy = NULL;
360    STACK_OF(OPENSSL_STRING) *files = NULL;
361
362    if (app_access(dirname, W_OK) < 0) {
363        BIO_printf(bio_err, "Skipping %s, can't write\n", dirname);
364        return 1;
365    }
366    dirlen = strlen(dirname);
367    if (dirlen != 0 && !ends_with_dirsep(dirname)) {
368        pathsep = "/";
369        dirlen++;
370    }
371
372    if (verbose)
373        BIO_printf(bio_out, "Doing %s\n", dirname);
374
375    if ((files = sk_OPENSSL_STRING_new(sk_strcmp)) == NULL) {
376        BIO_printf(bio_err, "Skipping %s, out of memory\n", dirname);
377        errs = 1;
378        goto err;
379    }
380    while ((filename = OPENSSL_DIR_read(&d, dirname)) != NULL) {
381        size_t fname_len = strlen(filename);
382
383        if ((copy = OPENSSL_strdup(filename)) == NULL
384                || sk_OPENSSL_STRING_push(files, copy) == 0) {
385            OPENSSL_free(copy);
386            OPENSSL_DIR_end(&d);
387            BIO_puts(bio_err, "out of memory\n");
388            errs = 1;
389            goto err;
390        }
391        if (fname_len > fname_max_len)
392            fname_max_len = fname_len;
393    }
394    OPENSSL_DIR_end(&d);
395    sk_OPENSSL_STRING_sort(files);
396
397    buflen = dirlen + fname_max_len + 1;
398    buf = app_malloc(buflen, "filename buffer");
399
400    numfiles = sk_OPENSSL_STRING_num(files);
401    for (n = 0; n < numfiles; ++n) {
402        filename = sk_OPENSSL_STRING_value(files, n);
403        if (BIO_snprintf(buf, buflen, "%s%s%s",
404                         dirname, pathsep, filename) >= buflen)
405            continue;
406        if (lstat(buf, &st) < 0)
407            continue;
408        if (S_ISLNK(st.st_mode) && handle_symlink(filename, buf) == 0)
409            continue;
410        errs += do_file(filename, buf, h);
411    }
412
413    for (i = 0; i < OSSL_NELEM(hash_table); i++) {
414        for (bp = hash_table[i]; bp; bp = nextbp) {
415            nextbp = bp->next;
416            nextid = 0;
417            memset(idmask, 0, (bp->num_needed + 7) / 8);
418            for (ep = bp->first_entry; ep; ep = ep->next)
419                if (ep->old_id < bp->num_needed)
420                    bit_set(idmask, ep->old_id);
421
422            for (ep = bp->first_entry; ep; ep = nextep) {
423                nextep = ep->next;
424                if (ep->old_id < bp->num_needed) {
425                    /* Link exists, and is used as-is */
426                    BIO_snprintf(buf, buflen, "%08x.%s%d", bp->hash,
427                                 suffixes[bp->type], ep->old_id);
428                    if (verbose)
429                        BIO_printf(bio_out, "link %s -> %s\n",
430                                   ep->filename, buf);
431                } else if (ep->need_symlink) {
432                    /* New link needed (it may replace something) */
433                    while (bit_isset(idmask, nextid))
434                        nextid++;
435
436                    BIO_snprintf(buf, buflen, "%s%s%08x.%s%d",
437                                 dirname, pathsep, bp->hash,
438                                 suffixes[bp->type], nextid);
439                    if (verbose)
440                        BIO_printf(bio_out, "link %s -> %s\n",
441                                   ep->filename, &buf[dirlen]);
442                    if (unlink(buf) < 0 && errno != ENOENT) {
443                        BIO_printf(bio_err,
444                                   "%s: Can't unlink %s, %s\n",
445                                   opt_getprog(), buf, strerror(errno));
446                        errs++;
447                    }
448                    if (symlink(ep->filename, buf) < 0) {
449                        BIO_printf(bio_err,
450                                   "%s: Can't symlink %s, %s\n",
451                                   opt_getprog(), ep->filename,
452                                   strerror(errno));
453                        errs++;
454                    }
455                    bit_set(idmask, nextid);
456                } else if (remove_links) {
457                    /* Link to be deleted */
458                    BIO_snprintf(buf, buflen, "%s%s%08x.%s%d",
459                                 dirname, pathsep, bp->hash,
460                                 suffixes[bp->type], ep->old_id);
461                    if (verbose)
462                        BIO_printf(bio_out, "unlink %s\n",
463                                   &buf[dirlen]);
464                    if (unlink(buf) < 0 && errno != ENOENT) {
465                        BIO_printf(bio_err,
466                                   "%s: Can't unlink %s, %s\n",
467                                   opt_getprog(), buf, strerror(errno));
468                        errs++;
469                    }
470                }
471                OPENSSL_free(ep->filename);
472                OPENSSL_free(ep);
473            }
474            OPENSSL_free(bp);
475        }
476        hash_table[i] = NULL;
477    }
478
479 err:
480    sk_OPENSSL_STRING_pop_free(files, str_free);
481    OPENSSL_free(buf);
482    return errs;
483}
484
485typedef enum OPTION_choice {
486    OPT_COMMON,
487    OPT_COMPAT, OPT_OLD, OPT_N, OPT_VERBOSE,
488    OPT_PROV_ENUM
489} OPTION_CHOICE;
490
491const OPTIONS rehash_options[] = {
492    {OPT_HELP_STR, 1, '-', "Usage: %s [options] [directory...]\n"},
493
494    OPT_SECTION("General"),
495    {"help", OPT_HELP, '-', "Display this summary"},
496    {"h", OPT_HELP, '-', "Display this summary"},
497    {"compat", OPT_COMPAT, '-', "Create both new- and old-style hash links"},
498    {"old", OPT_OLD, '-', "Use old-style hash to generate links"},
499    {"n", OPT_N, '-', "Do not remove existing links"},
500
501    OPT_SECTION("Output"),
502    {"v", OPT_VERBOSE, '-', "Verbose output"},
503
504    OPT_PROV_OPTIONS,
505
506    OPT_PARAMETERS(),
507    {"directory", 0, 0, "One or more directories to process (optional)"},
508    {NULL}
509};
510
511
512int rehash_main(int argc, char **argv)
513{
514    const char *env, *prog;
515    char *e, *m;
516    int errs = 0;
517    OPTION_CHOICE o;
518    enum Hash h = HASH_NEW;
519
520    prog = opt_init(argc, argv, rehash_options);
521    while ((o = opt_next()) != OPT_EOF) {
522        switch (o) {
523        case OPT_EOF:
524        case OPT_ERR:
525            BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
526            goto end;
527        case OPT_HELP:
528            opt_help(rehash_options);
529            goto end;
530        case OPT_COMPAT:
531            h = HASH_BOTH;
532            break;
533        case OPT_OLD:
534            h = HASH_OLD;
535            break;
536        case OPT_N:
537            remove_links = 0;
538            break;
539        case OPT_VERBOSE:
540            verbose = 1;
541            break;
542        case OPT_PROV_CASES:
543            if (!opt_provider(o))
544                goto end;
545            break;
546        }
547    }
548
549    /* Optional arguments are directories to scan. */
550    argc = opt_num_rest();
551    argv = opt_rest();
552
553    evpmd = EVP_sha1();
554    evpmdsize = EVP_MD_get_size(evpmd);
555
556    if (*argv != NULL) {
557        while (*argv != NULL)
558            errs += do_dir(*argv++, h);
559    } else if ((env = getenv(X509_get_default_cert_dir_env())) != NULL) {
560        char lsc[2] = { LIST_SEPARATOR_CHAR, '\0' };
561        m = OPENSSL_strdup(env);
562        for (e = strtok(m, lsc); e != NULL; e = strtok(NULL, lsc))
563            errs += do_dir(e, h);
564        OPENSSL_free(m);
565    } else {
566        errs += do_dir(X509_get_default_cert_dir(), h);
567    }
568
569 end:
570    return errs;
571}
572
573#else
574const OPTIONS rehash_options[] = {
575    {NULL}
576};
577
578int rehash_main(int argc, char **argv)
579{
580    BIO_printf(bio_err, "Not available; use c_rehash script\n");
581    return 1;
582}
583
584#endif /* defined(OPENSSL_SYS_UNIX) || defined(__APPLE__) */
585