From a5c32cff1f56afe6f0c6c70d91a88a7a8238b2d7 Mon Sep 17 00:00:00 2001 From: Harald Hoyer Date: Thu, 14 Feb 2013 12:26:13 +0100 Subject: honor SELinux labels, when creating and writing config files Also split out some fileio functions to fileio.c and provide a SELinux aware pendant in fileio-label.c see https://bugzilla.redhat.com/show_bug.cgi?id=881577 --- src/shared/fileio.c | 383 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 383 insertions(+) create mode 100644 src/shared/fileio.c (limited to 'src/shared/fileio.c') diff --git a/src/shared/fileio.c b/src/shared/fileio.c new file mode 100644 index 0000000000..4e6ff16045 --- /dev/null +++ b/src/shared/fileio.c @@ -0,0 +1,383 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright 2010 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see . +***/ + +#include +#include "fileio.h" +#include "util.h" +#include "strv.h" + +int write_one_line_file(const char *fn, const char *line) { + _cleanup_fclose_ FILE *f = NULL; + + assert(fn); + assert(line); + + f = fopen(fn, "we"); + if (!f) + return -errno; + + errno = 0; + if (fputs(line, f) < 0) + return errno ? -errno : -EIO; + + if (!endswith(line, "\n")) + fputc('\n', f); + + fflush(f); + + if (ferror(f)) + return errno ? -errno : -EIO; + + return 0; +} + +int write_one_line_file_atomic(const char *fn, const char *line) { + _cleanup_fclose_ FILE *f = NULL; + _cleanup_free_ char *p = NULL; + int r; + + assert(fn); + assert(line); + + r = fopen_temporary(fn, &f, &p); + if (r < 0) + return r; + + fchmod_umask(fileno(f), 0644); + + errno = 0; + if (fputs(line, f) < 0) { + r = -errno; + goto finish; + } + + if (!endswith(line, "\n")) + fputc('\n', f); + + fflush(f); + + if (ferror(f)) + r = errno ? -errno : -EIO; + else { + if (rename(p, fn) < 0) + r = -errno; + else + r = 0; + } + +finish: + if (r < 0) + unlink(p); + + return r; +} + +int read_one_line_file(const char *fn, char **line) { + _cleanup_fclose_ FILE *f = NULL; + char t[LINE_MAX], *c; + + assert(fn); + assert(line); + + f = fopen(fn, "re"); + if (!f) + return -errno; + + if (!fgets(t, sizeof(t), f)) { + + if (ferror(f)) + return errno ? -errno : -EIO; + + t[0] = 0; + } + + c = strdup(t); + if (!c) + return -ENOMEM; + truncate_nl(c); + + *line = c; + return 0; +} + +int read_full_file(const char *fn, char **contents, size_t *size) { + _cleanup_fclose_ FILE *f = NULL; + size_t n, l; + _cleanup_free_ char *buf = NULL; + struct stat st; + + assert(fn); + assert(contents); + + f = fopen(fn, "re"); + if (!f) + return -errno; + + if (fstat(fileno(f), &st) < 0) + return -errno; + + /* Safety check */ + if (st.st_size > 4*1024*1024) + return -E2BIG; + + n = st.st_size > 0 ? st.st_size : LINE_MAX; + l = 0; + + for (;;) { + char *t; + size_t k; + + t = realloc(buf, n+1); + if (!t) + return -ENOMEM; + + buf = t; + k = fread(buf + l, 1, n - l, f); + + if (k <= 0) { + if (ferror(f)) + return -errno; + + break; + } + + l += k; + n *= 2; + + /* Safety check */ + if (n > 4*1024*1024) + return -E2BIG; + } + + buf[l] = 0; + *contents = buf; + buf = NULL; + + if (size) + *size = l; + + return 0; +} + +int parse_env_file( + const char *fname, + const char *separator, ...) { + + int r = 0; + char *contents = NULL, *p; + + assert(fname); + assert(separator); + + if ((r = read_full_file(fname, &contents, NULL)) < 0) + return r; + + p = contents; + for (;;) { + const char *key = NULL; + + p += strspn(p, separator); + p += strspn(p, WHITESPACE); + + if (!*p) + break; + + if (!strchr(COMMENTS, *p)) { + va_list ap; + char **value; + + va_start(ap, separator); + while ((key = va_arg(ap, char *))) { + size_t n; + char *v; + + value = va_arg(ap, char **); + + n = strlen(key); + if (!strneq(p, key, n) || + p[n] != '=') + continue; + + p += n + 1; + n = strcspn(p, separator); + + if (n >= 2 && + strchr(QUOTES, p[0]) && + p[n-1] == p[0]) + v = strndup(p+1, n-2); + else + v = strndup(p, n); + + if (!v) { + r = -ENOMEM; + va_end(ap); + goto fail; + } + + if (v[0] == '\0') { + /* return empty value strings as NULL */ + free(v); + v = NULL; + } + + free(*value); + *value = v; + + p += n; + + r ++; + break; + } + va_end(ap); + } + + if (!key) + p += strcspn(p, separator); + } + +fail: + free(contents); + return r; +} + +int load_env_file(const char *fname, char ***rl) { + + _cleanup_fclose_ FILE *f; + _cleanup_strv_free_ char **m = NULL; + _cleanup_free_ char *c = NULL; + + assert(fname); + assert(rl); + + /* This reads an environment file, but will not complain about + * any invalid assignments, that needs to be done by the + * caller */ + + f = fopen(fname, "re"); + if (!f) + return -errno; + + while (!feof(f)) { + char l[LINE_MAX], *p, *cs, *b; + + if (!fgets(l, sizeof(l), f)) { + if (ferror(f)) + return -errno; + + /* The previous line was a continuation line? + * Let's process it now, before we leave the + * loop */ + if (c) + goto process; + + break; + } + + /* Is this a continuation line? If so, just append + * this to c, and go to next line right-away */ + cs = endswith(l, "\\\n"); + if (cs) { + *cs = '\0'; + b = strappend(c, l); + if (!b) + return -ENOMEM; + + free(c); + c = b; + continue; + } + + /* If the previous line was a continuation line, + * append the current line to it */ + if (c) { + b = strappend(c, l); + if (!b) + return -ENOMEM; + + free(c); + c = b; + } + + process: + p = strstrip(c ? c : l); + + if (*p && !strchr(COMMENTS, *p)) { + _cleanup_free_ char *u; + int k; + + u = normalize_env_assignment(p); + if (!u) + return -ENOMEM; + + k = strv_extend(&m, u); + if (k < 0) + return -ENOMEM; + } + + free(c); + c = NULL; + } + + *rl = m; + m = NULL; + + return 0; +} + +int write_env_file(const char *fname, char **l) { + char **i, *p; + FILE *f; + int r; + + r = fopen_temporary(fname, &f, &p); + if (r < 0) + return r; + + fchmod_umask(fileno(f), 0644); + + errno = 0; + STRV_FOREACH(i, l) { + fputs(*i, f); + fputc('\n', f); + } + + fflush(f); + + if (ferror(f)) { + if (errno != 0) + r = -errno; + else + r = -EIO; + } else { + if (rename(p, fname) < 0) + r = -errno; + else + r = 0; + } + + if (r < 0) + unlink(p); + + fclose(f); + free(p); + + return r; +} -- cgit v1.2.3-54-g00ecf