diff options
Diffstat (limited to 'common/envfs-core.c')
-rw-r--r-- | common/envfs-core.c | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/common/envfs-core.c b/common/envfs-core.c new file mode 100644 index 0000000000..20b3e647d3 --- /dev/null +++ b/common/envfs-core.c @@ -0,0 +1,200 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2019 Albert Schwarzkopf <a.schwarzkopf@phytec.de>, PHYTEC Messtechnik GmbH + * Copyright (c) 2007 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix + */ + +/** + * @file + * @brief Environment handling support (host and target) + * + * Important: This file will also be used on the host to create + * the default environment when building the barebox binary. So + * do not add any new barebox related functions here! + */ +#define pr_fmt(fmt) "envfs: " fmt + +#ifdef __BAREBOX__ +#include <common.h> +#include <fs.h> +#include <crc.h> +#include <envfs.h> +#include <libbb.h> +#include <libgen.h> +#include <environment.h> +#include <libfile.h> +#else +#define pr_info(fmt, ...) printf(pr_fmt(fmt), ##__VA_ARGS__) +#define pr_warn(fmt, ...) printf(pr_fmt(fmt), ##__VA_ARGS__) +#endif + +static int dir_remove_action(const char *filename, struct stat *statbuf, + void *userdata, int depth) +{ + if (!depth) + return 1; + + rmdir(filename); + + return 1; +} + +int envfs_check_super(struct envfs_super *super, size_t *size) +{ + if (ENVFS_32(super->magic) != ENVFS_MAGIC) { + pr_info("no envfs (magic mismatch) - envfs never written?\n"); + return -EIO; + } + + if (crc32(0, super, sizeof(*super) - 4) != ENVFS_32(super->sb_crc)) { + pr_warn("wrong crc on env superblock\n"); + return -EIO; + } + + if (super->major < ENVFS_MAJOR) + pr_info("version %d.%d loaded into %d.%d\n", + super->major, super->minor, + ENVFS_MAJOR, ENVFS_MINOR); + + *size = ENVFS_32(super->size); + + return 0; +} + +int envfs_check_data(struct envfs_super *super, const void *buf, size_t size) +{ + uint32_t crc; + + crc = crc32(0, buf, size); + if (crc != ENVFS_32(super->crc)) { + pr_warn("wrong crc on env\n"); + return -EIO; + } + + return 0; +} + +int envfs_load_data(struct envfs_super *super, void *buf, size_t size, + const char *dir, unsigned flags) +{ + int fd, ret = 0; + char *str, *tmp; + int headerlen_full; + /* for envfs < 1.0 */ + struct envfs_inode_end inode_end_dummy; + struct stat s; + + inode_end_dummy.mode = ENVFS_32(S_IRWXU | S_IRWXG | S_IRWXO); + inode_end_dummy.magic = ENVFS_32(ENVFS_INODE_END_MAGIC); + + while (size) { + struct envfs_inode *inode; + struct envfs_inode_end *inode_end; + uint32_t inode_size, inode_headerlen, namelen; + + inode = buf; + buf += sizeof(struct envfs_inode); + + if (ENVFS_32(inode->magic) != ENVFS_INODE_MAGIC) { + pr_warn("wrong magic\n"); + ret = -EIO; + goto out; + } + inode_size = ENVFS_32(inode->size); + inode_headerlen = ENVFS_32(inode->headerlen); + namelen = strlen(inode->data) + 1; + if (super->major < 1) + inode_end = &inode_end_dummy; + else + inode_end = buf + PAD4(namelen); + + debug("loading %s size %d namelen %d headerlen %d\n", inode->data, + inode_size, namelen, inode_headerlen); + + str = concat_path_file(dir, inode->data); + + headerlen_full = PAD4(inode_headerlen); + buf += headerlen_full; + + if (ENVFS_32(inode_end->magic) != ENVFS_INODE_END_MAGIC) { + printf("envfs: wrong inode_end_magic\n"); + ret = -EIO; + goto out; + } + + tmp = strdup(str); + make_directory(dirname(tmp)); + free(tmp); + + ret = stat(str, &s); + if (!ret && (flags & ENV_FLAG_NO_OVERWRITE)) { + printf("skip %s\n", str); + goto skip; + } + + if (S_ISLNK(ENVFS_32(inode_end->mode))) { + debug("symlink: %s -> %s\n", str, (char*)buf); + if (!strcmp(buf, basename(str))) { + unlink(str); + } else { + if (!ret) + unlink(str); + + ret = symlink(buf, str); + if (ret < 0) + printf("symlink: %s -> %s : %s\n", + str, (char*)buf, strerror(-errno)); + } + free(str); + } else { + fd = open(str, O_WRONLY | O_CREAT | O_TRUNC, 0644); + free(str); + if (fd < 0) { + printf("Open %m\n"); + ret = fd; + goto out; + } + + ret = write(fd, buf, inode_size); + if (ret < inode_size) { + perror("write"); + ret = -errno; + close(fd); + goto out; + } + close(fd); + } +skip: + buf += PAD4(inode_size); + size -= headerlen_full + PAD4(inode_size) + + sizeof(struct envfs_inode); + } + + recursive_action(dir, ACTION_RECURSE | ACTION_DEPTHFIRST, NULL, + dir_remove_action, NULL, 0); + + ret = 0; +out: + return ret; +} + +int envfs_load_from_buf(void *buf, int len, const char *dir, unsigned flags) +{ + int ret; + size_t size; + struct envfs_super *super = buf; + + buf = super + 1; + + ret = envfs_check_super(super, &size); + if (ret) + return ret; + + ret = envfs_check_data(super, buf, size); + if (ret) + return ret; + + ret = envfs_load_data(super, buf, size, dir, flags); + + return ret; +} |