diff options
Diffstat (limited to 'crond/rdcron.c')
| -rw-r--r-- | crond/rdcron.c | 503 |
1 files changed, 503 insertions, 0 deletions
diff --git a/crond/rdcron.c b/crond/rdcron.c new file mode 100644 index 0000000..8781a6f --- /dev/null +++ b/crond/rdcron.c @@ -0,0 +1,503 @@ +/* SPDX-License-Identifier: GPL-3.0-or-later */ +/* + * Copyright (C) 2018 - David Oberhollenzer + * + * This program 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. + * + * This program 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 this program. If not, see <https://www.gnu.org/licenses/>. + */ +#include <sys/types.h> +#include <sys/stat.h> +#include <unistd.h> +#include <string.h> +#include <stdlib.h> +#include <limits.h> +#include <stdio.h> +#include <errno.h> +#include <fcntl.h> +#include <ctype.h> +#include <pwd.h> +#include <grp.h> + +#include "crontab.h" +#include "libcfg.h" +#include "util.h" + + +static const enum_map_t weekday[] = { + { "MON", 1 }, + { "TUE", 2 }, + { "WED", 3 }, + { "THU", 4 }, + { "FRI", 5 }, + { "SAT", 6 }, + { "SUN", 0 }, +}; + +static const enum_map_t month[] = { + { "JAN", 1 }, + { "FEB", 2 }, + { "MAR", 3 }, + { "APR", 4 }, + { "MAY", 5 }, + { "JUN", 6 }, + { "JUL", 7 }, + { "AUG", 8 }, + { "SEP", 9 }, + { "OCT", 10 }, + { "NOV", 11 }, + { "DEC", 12 }, +}; + +static const struct { + const char *macro; + crontab_t tab; +} intervals[] = { + { + .macro = "yearly", + .tab = { + .minute = 0x01, + .hour = 0x01, + .dayofmonth = 0x01, + .month = 0x01, + .dayofweek = 0xFF + }, + }, { + .macro = "annually", + .tab = { + .minute = 0x01, + .hour = 0x01, + .dayofmonth = 0x01, + .month = 0x01, + .dayofweek = 0xFF + }, + }, { + .macro = "monthly", + .tab = { + .minute = 0x01, + .hour = 0x01, + .dayofmonth = 0x01, + .month = 0xFFFF, + .dayofweek = 0xFF + }, + }, { + .macro = "weekly", + .tab = { + .minute = 0x01, + .hour = 0x01, + .dayofmonth = 0xFFFFFFFF, + .month = 0xFFFF, + .dayofweek = 0x01 + }, + }, { + .macro = "daily", + .tab = { + .minute = 0x01, + .hour = 0x01, + .dayofmonth = 0xFFFFFFFF, + .month = 0xFFFF, + .dayofweek = 0xFF + }, + }, { + .macro = "hourly", + .tab = { + .minute = 0x01, + .hour = 0xFFFFFFFF, + .dayofmonth = 0xFFFFFFFF, + .month = 0xFFFF, + .dayofweek = 0xFF + }, + }, +}; + +/*****************************************************************************/ + +static int try_unescape(char *arg, rdline_t *rd) +{ + if (unescape(arg)) { + fprintf(stderr, "%s: %zu: malformed string constant\n", + rd->filename, rd->lineno); + return -1; + } + return 0; +} + +static char *try_strdup(const char *str, rdline_t *rd) +{ + char *out = strdup(str); + + if (out == NULL) { + fprintf(stderr, "%s: %zu: out of memory\n", + rd->filename, rd->lineno); + } + return out; +} + +static char *readnum(char *line, int *out, int minval, int maxval, + const enum_map_t *mnemonic, rdline_t *rd) +{ + int i, temp, value = 0; + const enum_map_t *ev; + + if (!isdigit(*line)) { + if (!mnemonic) + goto fail_mn; + + for (i = 0; isalnum(line[i]); ++i) + ; + if (i == 0) + goto fail_mn; + + temp = line[i]; + line[i] = '\0'; + ev = enum_by_name(mnemonic, line); + if (!ev) { + fprintf(stderr, "%s: %zu: unexpected '%s'", + rd->filename, rd->lineno, line); + } + line[i] = temp; + if (!ev) + return NULL; + *out = ev->value; + return line + i; + } + + while (isdigit(*line)) { + i = ((*(line++)) - '0'); + if (value > (maxval - i) / 10) + goto fail_of; + value = value * 10 + i; + } + + if (value < minval) + goto fail_uf; + + *out = value; + return line; +fail_of: + fprintf(stderr, "%s: %zu: value exceeds maximum (%d > %d)\n", + rd->filename, rd->lineno, value, maxval); + return NULL; +fail_uf: + fprintf(stderr, "%s: %zu: value too small (%d < %d)\n", + rd->filename, rd->lineno, value, minval); + return NULL; +fail_mn: + fprintf(stderr, "%s: %zu: expected numeric value", + rd->filename, rd->lineno); + return NULL; +} + +static char *readfield(char *line, uint64_t *out, int minval, int maxval, + const enum_map_t *mnemonic, rdline_t *rd) +{ + int value, endvalue, step; + uint64_t v = 0; +next: + if (*line == '*') { + ++line; + value = minval; + endvalue = maxval; + } else { + line = readnum(line, &value, minval, maxval, mnemonic, rd); + if (!line) + goto fail; + + if (*line == '-') { + line = readnum(line + 1, &endvalue, minval, maxval, + mnemonic, rd); + if (!line) + goto fail; + } else { + endvalue = value; + } + } + + if (endvalue < value) + goto fail; + + if (*line == '/') { + line = readnum(line + 1, &step, 1, maxval + 1, NULL, rd); + if (!line) + goto fail; + } else { + step = 1; + } + + while (value <= endvalue) { + v |= 1UL << (unsigned long)(value - minval); + value += step; + } + + if (*line == ',' || *line == ' ') { + ++line; + goto next; + } + + if (*line != '\0') + goto fail; + + *out = v; + return line; +fail: + fprintf(stderr, "%s: %zu: invalid time range expression\n", + rd->filename, rd->lineno); + return NULL; +} + +/*****************************************************************************/ + +static int cron_exec(void *user, char *arg, rdline_t *rd, int flags) +{ + crontab_t *cron = user; + exec_t *e, *end; + (void)flags; + + e = calloc(1, sizeof(*e) + strlen(arg) + 1); + if (e == NULL) { + fprintf(stderr, "%s: %zu: out of memory\n", + rd->filename, rd->lineno); + return -1; + } + + strcpy(e->args, arg); + + e->argc = pack_argv(e->args); + if (e->argc < 0) { + fprintf(stderr, "%s: %zu: malformed string constant\n", + rd->filename, rd->lineno); + return -1; + } + + if (cron->exec == NULL) { + cron->exec = e; + } else { + for (end = cron->exec; end->next != NULL; end = end->next) + ; + end->next = e; + } + return 0; +} + +static int cron_hour(void *user, char *arg, rdline_t *rd, int flags) +{ + crontab_t *cron = user; + uint64_t value; + (void)flags; + + if (!readfield(arg, &value, 0, 23, NULL, rd)) + return -1; + + cron->hour = value; + return 0; +} + +static int cron_minute(void *user, char *arg, rdline_t *rd, int flags) +{ + crontab_t *cron = user; + uint64_t value; + (void)flags; + + if (!readfield(arg, &value, 0, 59, NULL, rd)) + return -1; + + cron->minute = value; + return 0; +} + +static int cron_dayofmonth(void *user, char *arg, rdline_t *rd, int flags) +{ + crontab_t *cron = user; + uint64_t value; + (void)flags; + + if (!readfield(arg, &value, 1, 31, NULL, rd)) + return -1; + + cron->dayofmonth = value; + return 0; +} + +static int cron_dayofweek(void *user, char *arg, rdline_t *rd, int flags) +{ + crontab_t *cron = user; + uint64_t value; + (void)flags; + + if (!readfield(arg, &value, 0, 6, weekday, rd)) + return -1; + + cron->dayofweek = value; + return 0; +} + +static int cron_month(void *user, char *arg, rdline_t *rd, int flags) +{ + crontab_t *cron = user; + uint64_t value; + (void)flags; + + if (!readfield(arg, &value, 1, 12, month, rd)) + return -1; + + cron->month = value; + return 0; +} + +static int cron_interval(void *user, char *arg, rdline_t *rd, int flags) +{ + crontab_t *cron = user; + size_t i; + (void)flags; + + for (i = 0; i < ARRAY_SIZE(intervals); ++i) { + if (!strcmp(intervals[i].macro, arg)) { + cron->minute = intervals[i].tab.minute; + cron->hour = intervals[i].tab.hour; + cron->dayofmonth = intervals[i].tab.dayofmonth; + cron->month = intervals[i].tab.month; + cron->dayofweek = intervals[i].tab.dayofweek; + return 0; + } + } + + fprintf(stderr, "%s: %zu: unknown interval '%s'\n", + rd->filename, rd->lineno, arg); + return -1; +} + +static int cron_user(void *user, char *arg, rdline_t *rd, int flags) +{ + crontab_t *cron = user; + struct passwd *pwd; + bool isnumeric; + char *ptr; + int value; + (void)flags; + + for (ptr = arg; isdigit(*ptr); ++ptr) + ; + + isnumeric = (*ptr == '\0'); + pwd = getpwnam(arg); + + if (pwd == NULL && !isnumeric) { + fprintf(stderr, "%s: %zu: unknown user '%s'\n", + rd->filename, rd->lineno, arg); + return -1; + } + + if (pwd != NULL) { + cron->uid = pwd->pw_uid; + } else { + if (readnum(arg, &value, 0, INT_MAX, NULL, rd)) + return -1; + cron->uid = value; + } + return 0; +} + +static int cron_group(void *user, char *arg, rdline_t *rd, int flags) +{ + crontab_t *cron = user; + struct group *group; + bool isnumeric; + char *ptr; + int value; + (void)flags; + + for (ptr = arg; isdigit(*ptr); ++ptr) + ; + + isnumeric = (*ptr == '\0'); + group = getgrnam(arg); + + if (group == NULL && !isnumeric) { + fprintf(stderr, "%s: %zu: unknown group '%s'\n", + rd->filename, rd->lineno, arg); + return -1; + } + + if (group != NULL) { + cron->gid = group->gr_gid; + } else { + if (readnum(arg, &value, 0, INT_MAX, NULL, rd)) + return -1; + cron->gid = value; + } + return 0; +} + +static int cron_tty(void *user, char *arg, rdline_t *rd, int flags) +{ + crontab_t *cron = user; + (void)flags; + + if (strncmp(arg, "truncate", 8) == 0 && isspace(arg[8])) { + cron->tty_truncate = 1; + arg += 8; + while (isspace(*arg)) + ++arg; + } + + if (try_unescape(arg, rd)) + return -1; + + cron->ctty = try_strdup(arg, rd); + return cron->ctty == NULL ? -1 : 0; +} + + + +static const cfg_param_t cron_params[] = { + { "hour", 0, cron_hour }, + { "minute", 0, cron_minute }, + { "dayofmonth", 0, cron_dayofmonth }, + { "dayofweek", 0, cron_dayofweek }, + { "month", 0, cron_month }, + { "interval", 0, cron_interval }, + { "user", 0, cron_user }, + { "group", 0, cron_group }, + { "tty", 0, cron_tty }, + { "exec", 1, cron_exec }, +}; + +crontab_t *rdcron(int dirfd, const char *filename) +{ + crontab_t *cron = NULL; + rdline_t rd; + int ret; + + if (rdline_init(&rd, dirfd, filename, 0, NULL)) + return NULL; + + cron = calloc(1, sizeof(*cron)); + if (cron == NULL) { + fputs("out of memory\n", stderr); + goto out; + } + + cron->minute = 0xFFFFFFFFFFFFFFFFUL; + cron->hour = 0xFFFFFFFF; + cron->dayofmonth = 0xFFFFFFFF; + cron->month = 0xFFFF; + cron->dayofweek = 0xFF; + + ret = rdcfg(cron, &rd, cron_params, ARRAY_SIZE(cron_params), 0); + if (ret) { + delcron(cron); + cron = NULL; + } +out: + rdline_cleanup(&rd); + return cron; +} |