diff options
Diffstat (limited to 'grub-core/commands/wildcard.c')
-rw-r--r-- | grub-core/commands/wildcard.c | 652 |
1 files changed, 652 insertions, 0 deletions
diff --git a/grub-core/commands/wildcard.c b/grub-core/commands/wildcard.c new file mode 100644 index 0000000..cc32903 --- /dev/null +++ b/grub-core/commands/wildcard.c @@ -0,0 +1,652 @@ +/* wildcard.c - Wildcard character expansion for GRUB script. */ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 2010 Free Software Foundation, Inc. + * + * GRUB is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * GRUB is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with GRUB. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <grub/mm.h> +#include <grub/fs.h> +#include <grub/env.h> +#include <grub/file.h> +#include <grub/device.h> +#include <grub/script_sh.h> +#include <grub/safemath.h> + +#include <regex.h> + +static inline int isregexop (char ch); +static char ** merge (char **lhs, char **rhs); +static char *make_dir (const char *prefix, const char *start, const char *end); +static int make_regex (const char *regex_start, const char *regex_end, + regex_t *regexp); +static void split_path (const char *path, const char **suffix_end, const char **regex_end); +static char ** match_devices (const regex_t *regexp, int noparts); +static char ** match_files (const char *prefix, const char *suffix_start, + const char *suffix_end, const regex_t *regexp); + +static grub_err_t wildcard_expand (const char *s, char ***strs); + +struct grub_script_wildcard_translator grub_filename_translator = { + .expand = wildcard_expand, +}; + +static char ** +merge (char **dest, char **ps) +{ + int i; + int j; + char **p; + grub_size_t sz; + + if (! dest) + return ps; + + if (! ps) + return dest; + + for (i = 0; dest[i]; i++) + ; + for (j = 0; ps[j]; j++) + ; + + if (grub_add (i, j, &sz) || + grub_add (sz, 1, &sz) || + grub_mul (sz, sizeof (char *), &sz)) + return dest; + + p = grub_realloc (dest, sz); + if (! p) + { + grub_free (dest); + grub_free (ps); + return 0; + } + + dest = p; + for (j = 0; ps[j]; j++) + dest[i++] = ps[j]; + dest[i] = 0; + + grub_free (ps); + return dest; +} + +static inline int +isregexop (char ch) +{ + return grub_strchr ("*.\\|+{}[]?", ch) ? 1 : 0; +} + +static char * +make_dir (const char *prefix, const char *start, const char *end) +{ + char ch; + unsigned i; + unsigned n; + char *result; + + i = grub_strlen (prefix); + n = i + end - start; + + result = grub_malloc (n + 1); + if (! result) + return 0; + + grub_strcpy (result, prefix); + while (start < end && (ch = *start++)) + if (ch == '\\' && isregexop (*start)) + result[i++] = *start++; + else + result[i++] = ch; + + result[i] = '\0'; + return result; +} + +static int +make_regex (const char *start, const char *end, regex_t *regexp) +{ + char ch; + int i = 0; + unsigned len = end - start; + char *buffer; + grub_size_t sz; + + /* Worst case size is (len * 2 + 2 + 1). */ + if (grub_mul (len, 2, &sz) || + grub_add (sz, 3, &sz)) + return 1; + + buffer = grub_malloc (sz); + if (! buffer) + return 1; + + buffer[i++] = '^'; + while (start < end) + { + /* XXX Only * and ? expansion for now. */ + switch ((ch = *start++)) + { + case '\\': + buffer[i++] = ch; + if (*start != '\0') + buffer[i++] = *start++; + break; + + case '.': + case '(': + case ')': + case '@': + case '+': + case '|': + case '{': + case '}': + case '[': + case ']': + buffer[i++] = '\\'; + buffer[i++] = ch; + break; + + case '*': + buffer[i++] = '.'; + buffer[i++] = '*'; + break; + + case '?': + buffer[i++] = '.'; + break; + + default: + buffer[i++] = ch; + } + } + buffer[i++] = '$'; + buffer[i] = '\0'; + grub_dprintf ("expand", "Regexp is %s\n", buffer); + + if (regcomp (regexp, buffer, RE_SYNTAX_GNU_AWK)) + { + grub_free (buffer); + return 1; + } + + grub_free (buffer); + return 0; +} + +/* Split `str' into two parts: (1) dirname that is regexop free (2) + dirname that has a regexop. */ +static void +split_path (const char *str, const char **noregexop, const char **regexop) +{ + char ch = 0; + int regex = 0; + + const char *end; + const char *split; /* points till the end of dirnaname that doesn't + need expansion. */ + + split = end = str; + while ((ch = *end)) + { + if (ch == '\\' && end[1]) + end++; + + else if (ch == '*' || ch == '?') + regex = 1; + + else if (ch == '/' && ! regex) + split = end + 1; /* forward to next regexop-free dirname */ + + else if (ch == '/' && regex) + break; /* stop at the first dirname with a regexop */ + + end++; + } + + *regexop = end; + if (! regex) + *noregexop = end; + else + *noregexop = split; +} + +/* Context for match_devices. */ +struct match_devices_ctx +{ + const regex_t *regexp; + int noparts; + int ndev; + char **devs; +}; + +/* Helper for match_devices. */ +static int +match_devices_iter (const char *name, void *data) +{ + struct match_devices_ctx *ctx = data; + char **t; + char *buffer; + grub_size_t sz; + + /* skip partitions if asked to. */ + if (ctx->noparts && grub_strchr (name, ',')) + return 0; + + buffer = grub_xasprintf ("(%s)", name); + if (! buffer) + return 1; + + grub_dprintf ("expand", "matching: %s\n", buffer); + if (regexec (ctx->regexp, buffer, 0, 0, 0)) + { + grub_dprintf ("expand", "not matched\n"); + fail: + grub_free (buffer); + return 0; + } + + if (grub_add (ctx->ndev, 2, &sz) || + grub_mul (sz, sizeof (char *), &sz)) + goto fail; + + t = grub_realloc (ctx->devs, sz); + if (! t) + { + grub_free (buffer); + return 1; + } + + ctx->devs = t; + ctx->devs[ctx->ndev++] = buffer; + ctx->devs[ctx->ndev] = 0; + return 0; +} + +static char ** +match_devices (const regex_t *regexp, int noparts) +{ + struct match_devices_ctx ctx = { + .regexp = regexp, + .noparts = noparts, + .ndev = 0, + .devs = 0 + }; + int i; + + if (grub_device_iterate (match_devices_iter, &ctx)) + goto fail; + + return ctx.devs; + + fail: + + for (i = 0; ctx.devs && ctx.devs[i]; i++) + grub_free (ctx.devs[i]); + + grub_free (ctx.devs); + + return 0; +} + +/* Context for match_files. */ +struct match_files_ctx +{ + const regex_t *regexp; + char **files; + unsigned nfile; + char *dir; +}; + +/* Helper for match_files. */ +static int +match_files_iter (const char *name, + const struct grub_dirhook_info *info __attribute__((unused)), + void *data) +{ + struct match_files_ctx *ctx = data; + char **t; + char *buffer; + grub_size_t sz; + + /* skip . and .. names */ + if (grub_strcmp(".", name) == 0 || grub_strcmp("..", name) == 0) + return 0; + + grub_dprintf ("expand", "matching: %s in %s\n", name, ctx->dir); + if (regexec (ctx->regexp, name, 0, 0, 0)) + return 0; + + grub_dprintf ("expand", "matched\n"); + + buffer = grub_xasprintf ("%s%s", ctx->dir, name); + if (! buffer) + return 1; + + if (grub_add (ctx->nfile, 2, &sz) || + grub_mul (sz, sizeof (char *), &sz)) + goto fail; + + t = grub_realloc (ctx->files, sz); + if (!t) + { + fail: + grub_free (buffer); + return 1; + } + + ctx->files = t; + ctx->files[ctx->nfile++] = buffer; + ctx->files[ctx->nfile] = 0; + return 0; +} + +static char ** +match_files (const char *prefix, const char *suffix, const char *end, + const regex_t *regexp) +{ + struct match_files_ctx ctx = { + .regexp = regexp, + .nfile = 0, + .files = 0 + }; + int i; + const char *path; + char *device_name; + grub_fs_t fs; + grub_device_t dev; + + dev = 0; + device_name = 0; + grub_error_push (); + + ctx.dir = make_dir (prefix, suffix, end); + if (! ctx.dir) + goto fail; + + device_name = grub_file_get_device_name (ctx.dir); + dev = grub_device_open (device_name); + if (! dev) + goto fail; + + fs = grub_fs_probe (dev); + if (! fs) + goto fail; + + if (ctx.dir[0] == '(') + { + path = grub_strchr (ctx.dir, ')'); + if (!path) + goto fail; + path++; + } + else + path = ctx.dir; + + if (fs->fs_dir (dev, path, match_files_iter, &ctx)) + goto fail; + + grub_free (ctx.dir); + grub_device_close (dev); + grub_free (device_name); + grub_error_pop (); + return ctx.files; + + fail: + + grub_free (ctx.dir); + + for (i = 0; ctx.files && ctx.files[i]; i++) + grub_free (ctx.files[i]); + + grub_free (ctx.files); + + if (dev) + grub_device_close (dev); + + grub_free (device_name); + + grub_error_pop (); + return 0; +} + +/* Context for check_file. */ +struct check_file_ctx +{ + const char *basename; + int found; +}; + +/* Helper for check_file. */ +static int +check_file_iter (const char *name, const struct grub_dirhook_info *info, + void *data) +{ + struct check_file_ctx *ctx = data; + + if (ctx->basename[0] == 0 + || (info->case_insensitive ? grub_strcasecmp (name, ctx->basename) == 0 + : grub_strcmp (name, ctx->basename) == 0)) + { + ctx->found = 1; + return 1; + } + + return 0; +} + +static int +check_file (const char *dir, const char *basename) +{ + struct check_file_ctx ctx = { + .basename = basename, + .found = 0 + }; + grub_fs_t fs; + grub_device_t dev; + const char *device_name, *path; + + device_name = grub_file_get_device_name (dir); + dev = grub_device_open (device_name); + if (! dev) + goto fail; + + fs = grub_fs_probe (dev); + if (! fs) + goto fail; + + if (dir[0] == '(') + { + path = grub_strchr (dir, ')'); + if (!path) + goto fail; + path++; + } + else + path = dir; + + fs->fs_dir (dev, path[0] ? path : "/", check_file_iter, &ctx); + if (grub_errno == 0 && basename[0] == 0) + ctx.found = 1; + + fail: + grub_errno = 0; + + return ctx.found; +} + +static void +unescape (char *out, const char *in, const char *end) +{ + char *optr; + const char *iptr; + + for (optr = out, iptr = in; iptr < end;) + { + if (*iptr == '\\' && iptr + 1 < end) + { + *optr++ = iptr[1]; + iptr += 2; + continue; + } + if (*iptr == '\\') + break; + *optr++ = *iptr++; + } + *optr = 0; +} + +static grub_err_t +wildcard_expand (const char *s, char ***strs) +{ + const char *start; + const char *regexop; + const char *noregexop; + char **paths = 0; + int had_regexp = 0; + + unsigned i; + regex_t regexp; + + *strs = 0; + if (s[0] != '/' && s[0] != '(' && s[0] != '*') + return 0; + + start = s; + while (*start) + { + split_path (start, &noregexop, ®exop); + + if (noregexop == regexop) + { + grub_dprintf ("expand", "no expansion needed\n"); + if (paths == 0) + { + paths = grub_malloc (sizeof (char *) * 2); + if (!paths) + goto fail; + paths[0] = grub_malloc (regexop - start + 1); + if (!paths[0]) + goto fail; + unescape (paths[0], start, regexop); + paths[1] = 0; + } + else + { + int j = 0; + for (i = 0; paths[i]; i++) + { + char *o, *oend; + char *n; + char *p; + o = paths[i]; + oend = o + grub_strlen (o); + n = grub_malloc ((oend - o) + (regexop - start) + 1); + if (!n) + goto fail; + grub_memcpy (n, o, oend - o); + + unescape (n + (oend - o), start, regexop); + if (had_regexp) + p = grub_strrchr (n, '/'); + else + p = 0; + if (!p) + { + grub_free (o); + paths[j++] = n; + continue; + } + *p = 0; + if (!check_file (n, p + 1)) + { + grub_dprintf ("expand", "file <%s> in <%s> not found\n", + p + 1, n); + grub_free (o); + grub_free (n); + continue; + } + *p = '/'; + grub_free (o); + paths[j++] = n; + } + if (j == 0) + { + grub_free (paths); + paths = 0; + goto done; + } + paths[j] = 0; + } + grub_dprintf ("expand", "paths[0] = `%s'\n", paths[0]); + start = regexop; + continue; + } + + if (make_regex (noregexop, regexop, ®exp)) + goto fail; + + had_regexp = 1; + + if (paths == 0) + { + if (start == noregexop) /* device part has regexop */ + paths = match_devices (®exp, *start != '('); + + else /* device part explicit wo regexop */ + paths = match_files ("", start, noregexop, ®exp); + } + else + { + char **r = 0; + + for (i = 0; paths[i]; i++) + { + char **p; + + p = match_files (paths[i], start, noregexop, ®exp); + grub_free (paths[i]); + if (! p) + continue; + + r = merge (r, p); + if (! r) + goto fail; + } + grub_free (paths); + paths = r; + } + + regfree (®exp); + if (! paths) + goto done; + + start = regexop; + } + + done: + + *strs = paths; + return 0; + + fail: + + for (i = 0; paths && paths[i]; i++) + grub_free (paths[i]); + grub_free (paths); + regfree (®exp); + return grub_errno; +} |