diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 15:35:18 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 15:35:18 +0000 |
commit | b750101eb236130cf056c675997decbac904cc49 (patch) | |
tree | a5df1a06754bdd014cb975c051c83b01c9a97532 /src/shared/base-filesystem.c | |
parent | Initial commit. (diff) | |
download | systemd-b750101eb236130cf056c675997decbac904cc49.tar.xz systemd-b750101eb236130cf056c675997decbac904cc49.zip |
Adding upstream version 252.22.upstream/252.22upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | src/shared/base-filesystem.c | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/src/shared/base-filesystem.c b/src/shared/base-filesystem.c new file mode 100644 index 0000000..5b4f674 --- /dev/null +++ b/src/shared/base-filesystem.c @@ -0,0 +1,199 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include <errno.h> +#include <fcntl.h> +#include <stdbool.h> +#include <stdlib.h> +#include <sys/stat.h> +#include <syslog.h> +#include <unistd.h> + +#include "alloc-util.h" +#include "architecture.h" +#include "base-filesystem.h" +#include "fd-util.h" +#include "log.h" +#include "macro.h" +#include "nulstr-util.h" +#include "path-util.h" +#include "string-util.h" +#include "umask-util.h" +#include "user-util.h" + +typedef struct BaseFilesystem { + const char *dir; /* directory or symlink to create */ + mode_t mode; + const char *target; /* if non-NULL create as symlink to this target */ + const char *exists; /* conditionalize this entry on existence of this file */ + bool ignore_failure; +} BaseFilesystem; + +static const BaseFilesystem table[] = { + { "bin", 0, "usr/bin\0", NULL }, + { "lib", 0, "usr/lib\0", NULL }, + { "root", 0750, NULL, NULL, true }, + { "sbin", 0, "usr/sbin\0", NULL }, + { "usr", 0755, NULL, NULL }, + { "var", 0755, NULL, NULL }, + { "etc", 0755, NULL, NULL }, + { "proc", 0755, NULL, NULL, true }, + { "sys", 0755, NULL, NULL, true }, + { "dev", 0755, NULL, NULL, true }, + + /* Various architecture ABIs define the path to the dynamic loader via the /lib64/ subdirectory of + * the root directory. When booting from an otherwise empty root file system (where only /usr/ has + * been mounted into) it is thus necessary to create a symlink pointing to the right subdirectory of + * /usr/ first — otherwise we couldn't invoke any dynamic binary. Let's detect this case here, and + * create the symlink as needed should it be missing. We prefer doing this consistently with Debian's + * multiarch logic, but support Fedora-style multilib too.*/ +#if defined(__aarch64__) + /* aarch64 ELF ABI actually says dynamic loader is in /lib/, but Fedora puts it in /lib64/ anyway and + * just symlinks /lib/ld-linux-aarch64.so.1 to ../lib64/ld-linux-aarch64.so.1. For this to work + * correctly, /lib64/ must be symlinked to /usr/lib64/. */ + { "lib64", 0, "usr/lib/"LIB_ARCH_TUPLE"\0" + "usr/lib64\0", "ld-linux-aarch64.so.1" }, +# define KNOW_LIB64_DIRS 1 +#elif defined(__alpha__) +#elif defined(__arc__) || defined(__tilegx__) +#elif defined(__arm__) + /* No /lib64 on arm. The linker is /lib/ld-linux-armhf.so.3. */ +# define KNOW_LIB64_DIRS 1 +#elif defined(__i386__) || defined(__x86_64__) + { "lib64", 0, "usr/lib/"LIB_ARCH_TUPLE"\0" + "usr/lib64\0", "ld-linux-x86-64.so.2" }, +# define KNOW_LIB64_DIRS 1 +#elif defined(__ia64__) +#elif defined(__loongarch64) +# define KNOW_LIB64_DIRS 1 +# if defined(__loongarch_double_float) + { "lib64", 0, "usr/lib/"LIB_ARCH_TUPLE"\0" + "usr/lib64\0", "ld-linux-loongarch-lp64d.so.1" }, +# elif defined(__loongarch_single_float) + { "lib64", 0, "usr/lib/"LIB_ARCH_TUPLE"\0" + "usr/lib64\0", "ld-linux-loongarch-lp64f.so.1" }, +# elif defined(__loongarch_soft_float) + { "lib64", 0, "usr/lib/"LIB_ARCH_TUPLE"\0" + "usr/lib64\0", "ld-linux-loongarch-lp64s.so.1" }, +# else +# error "Unknown LoongArch ABI" +# endif +#elif defined(__m68k__) + /* No link needed. */ +# define KNOW_LIB64_DIRS 1 +#elif defined(_MIPS_SIM) +# if _MIPS_SIM == _MIPS_SIM_ABI32 +# elif _MIPS_SIM == _MIPS_SIM_NABI32 +# elif _MIPS_SIM == _MIPS_SIM_ABI64 +# else +# error "Unknown MIPS ABI" +# endif +#elif defined(__powerpc__) +# if defined(__PPC64__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ + { "lib64", 0, "usr/lib/"LIB_ARCH_TUPLE"\0" + "usr/lib64\0", "ld64.so.2" }, +# define KNOW_LIB64_DIRS 1 +# elif defined(__powerpc64__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ + /* powerpc64-linux-gnu */ +# else + /* powerpc-linux-gnu */ +# endif +#elif defined(__riscv) +# if __riscv_xlen == 32 +# elif __riscv_xlen == 64 + /* Same situation as for aarch64 */ + { "lib64", 0, "usr/lib/"LIB_ARCH_TUPLE"\0" + "usr/lib64\0", "ld-linux-riscv64-lp64d.so.1" }, +# define KNOW_LIB64_DIRS 1 +# else +# error "Unknown RISC-V ABI" +# endif +#elif defined(__s390__) + /* s390-linux-gnu */ +#elif defined(__s390x__) + { "lib64", 0, "usr/lib/"LIB_ARCH_TUPLE"\0" + "usr/lib64\0", "ld-lsb-s390x.so.3" }, +# define KNOW_LIB64_DIRS 1 +#elif defined(__sparc__) +#endif + /* gcc doesn't allow pragma to be used within constructs, hence log about this separately below */ +}; + +#ifndef KNOW_LIB64_DIRS +# pragma message "Please add an entry above specifying whether your architecture uses /lib64/, /lib32/, or no such links." +#endif + +int base_filesystem_create(const char *root, uid_t uid, gid_t gid) { + _cleanup_close_ int fd = -1; + int r; + + fd = open(root, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|O_NOFOLLOW); + if (fd < 0) + return log_error_errno(errno, "Failed to open root file system: %m"); + + for (size_t i = 0; i < ELEMENTSOF(table); i++) { + if (faccessat(fd, table[i].dir, F_OK, AT_SYMLINK_NOFOLLOW) >= 0) + continue; + + if (table[i].target) { + const char *target = NULL, *s; + + /* check if one of the targets exists */ + NULSTR_FOREACH(s, table[i].target) { + if (faccessat(fd, s, F_OK, AT_SYMLINK_NOFOLLOW) < 0) + continue; + + /* check if a specific file exists at the target path */ + if (table[i].exists) { + _cleanup_free_ char *p = NULL; + + p = path_join(s, table[i].exists); + if (!p) + return log_oom(); + + if (faccessat(fd, p, F_OK, AT_SYMLINK_NOFOLLOW) < 0) + continue; + } + + target = s; + break; + } + + if (!target) + continue; + + if (symlinkat(target, fd, table[i].dir) < 0) { + log_full_errno(IN_SET(errno, EEXIST, EROFS) || table[i].ignore_failure ? LOG_DEBUG : LOG_ERR, errno, + "Failed to create symlink at %s/%s: %m", root, table[i].dir); + + if (IN_SET(errno, EEXIST, EROFS) || table[i].ignore_failure) + continue; + + return -errno; + } + + if (uid_is_valid(uid) || gid_is_valid(gid)) + if (fchownat(fd, table[i].dir, uid, gid, AT_SYMLINK_NOFOLLOW) < 0) + return log_error_errno(errno, "Failed to chown symlink at %s/%s: %m", root, table[i].dir); + + continue; + } + + RUN_WITH_UMASK(0000) + r = mkdirat(fd, table[i].dir, table[i].mode); + if (r < 0) { + log_full_errno(IN_SET(errno, EEXIST, EROFS) || table[i].ignore_failure ? LOG_DEBUG : LOG_ERR, errno, + "Failed to create directory at %s/%s: %m", root, table[i].dir); + + if (IN_SET(errno, EEXIST, EROFS) || table[i].ignore_failure) + continue; + + return -errno; + } + + if (uid_is_valid(uid) || gid_is_valid(gid)) + if (fchownat(fd, table[i].dir, uid, gid, AT_SYMLINK_NOFOLLOW) < 0) + return log_error_errno(errno, "Failed to chown directory at %s/%s: %m", root, table[i].dir); + } + + return 0; +} |