diff options
Diffstat (limited to 'usr/gen_init_cpio.c')
-rw-r--r-- | usr/gen_init_cpio.c | 688 |
1 files changed, 688 insertions, 0 deletions
diff --git a/usr/gen_init_cpio.c b/usr/gen_init_cpio.c new file mode 100644 index 0000000000..61230532fe --- /dev/null +++ b/usr/gen_init_cpio.c @@ -0,0 +1,688 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <stdio.h> +#include <stdlib.h> +#include <stdint.h> +#include <stdbool.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <string.h> +#include <unistd.h> +#include <time.h> +#include <fcntl.h> +#include <errno.h> +#include <ctype.h> +#include <limits.h> + +/* + * Original work by Jeff Garzik + * + * External file lists, symlink, pipe and fifo support by Thayne Harbaugh + * Hard link support by Luciano Rocha + */ + +#define xstr(s) #s +#define str(s) xstr(s) +#define MIN(a, b) ((a) < (b) ? (a) : (b)) + +static unsigned int offset; +static unsigned int ino = 721; +static time_t default_mtime; +static bool do_csum = false; + +struct file_handler { + const char *type; + int (*handler)(const char *line); +}; + +static void push_string(const char *name) +{ + unsigned int name_len = strlen(name) + 1; + + fputs(name, stdout); + putchar(0); + offset += name_len; +} + +static void push_pad (void) +{ + while (offset & 3) { + putchar(0); + offset++; + } +} + +static void push_rest(const char *name) +{ + unsigned int name_len = strlen(name) + 1; + unsigned int tmp_ofs; + + fputs(name, stdout); + putchar(0); + offset += name_len; + + tmp_ofs = name_len + 110; + while (tmp_ofs & 3) { + putchar(0); + offset++; + tmp_ofs++; + } +} + +static void push_hdr(const char *s) +{ + fputs(s, stdout); + offset += 110; +} + +static void cpio_trailer(void) +{ + char s[256]; + const char name[] = "TRAILER!!!"; + + sprintf(s, "%s%08X%08X%08lX%08lX%08X%08lX" + "%08X%08X%08X%08X%08X%08X%08X", + do_csum ? "070702" : "070701", /* magic */ + 0, /* ino */ + 0, /* mode */ + (long) 0, /* uid */ + (long) 0, /* gid */ + 1, /* nlink */ + (long) 0, /* mtime */ + 0, /* filesize */ + 0, /* major */ + 0, /* minor */ + 0, /* rmajor */ + 0, /* rminor */ + (unsigned)strlen(name)+1, /* namesize */ + 0); /* chksum */ + push_hdr(s); + push_rest(name); + + while (offset % 512) { + putchar(0); + offset++; + } +} + +static int cpio_mkslink(const char *name, const char *target, + unsigned int mode, uid_t uid, gid_t gid) +{ + char s[256]; + + if (name[0] == '/') + name++; + sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX" + "%08X%08X%08X%08X%08X%08X%08X", + do_csum ? "070702" : "070701", /* magic */ + ino++, /* ino */ + S_IFLNK | mode, /* mode */ + (long) uid, /* uid */ + (long) gid, /* gid */ + 1, /* nlink */ + (long) default_mtime, /* mtime */ + (unsigned)strlen(target)+1, /* filesize */ + 3, /* major */ + 1, /* minor */ + 0, /* rmajor */ + 0, /* rminor */ + (unsigned)strlen(name) + 1,/* namesize */ + 0); /* chksum */ + push_hdr(s); + push_string(name); + push_pad(); + push_string(target); + push_pad(); + return 0; +} + +static int cpio_mkslink_line(const char *line) +{ + char name[PATH_MAX + 1]; + char target[PATH_MAX + 1]; + unsigned int mode; + int uid; + int gid; + int rc = -1; + + if (5 != sscanf(line, "%" str(PATH_MAX) "s %" str(PATH_MAX) "s %o %d %d", name, target, &mode, &uid, &gid)) { + fprintf(stderr, "Unrecognized dir format '%s'", line); + goto fail; + } + rc = cpio_mkslink(name, target, mode, uid, gid); + fail: + return rc; +} + +static int cpio_mkgeneric(const char *name, unsigned int mode, + uid_t uid, gid_t gid) +{ + char s[256]; + + if (name[0] == '/') + name++; + sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX" + "%08X%08X%08X%08X%08X%08X%08X", + do_csum ? "070702" : "070701", /* magic */ + ino++, /* ino */ + mode, /* mode */ + (long) uid, /* uid */ + (long) gid, /* gid */ + 2, /* nlink */ + (long) default_mtime, /* mtime */ + 0, /* filesize */ + 3, /* major */ + 1, /* minor */ + 0, /* rmajor */ + 0, /* rminor */ + (unsigned)strlen(name) + 1,/* namesize */ + 0); /* chksum */ + push_hdr(s); + push_rest(name); + return 0; +} + +enum generic_types { + GT_DIR, + GT_PIPE, + GT_SOCK +}; + +struct generic_type { + const char *type; + mode_t mode; +}; + +static const struct generic_type generic_type_table[] = { + [GT_DIR] = { + .type = "dir", + .mode = S_IFDIR + }, + [GT_PIPE] = { + .type = "pipe", + .mode = S_IFIFO + }, + [GT_SOCK] = { + .type = "sock", + .mode = S_IFSOCK + } +}; + +static int cpio_mkgeneric_line(const char *line, enum generic_types gt) +{ + char name[PATH_MAX + 1]; + unsigned int mode; + int uid; + int gid; + int rc = -1; + + if (4 != sscanf(line, "%" str(PATH_MAX) "s %o %d %d", name, &mode, &uid, &gid)) { + fprintf(stderr, "Unrecognized %s format '%s'", + line, generic_type_table[gt].type); + goto fail; + } + mode |= generic_type_table[gt].mode; + rc = cpio_mkgeneric(name, mode, uid, gid); + fail: + return rc; +} + +static int cpio_mkdir_line(const char *line) +{ + return cpio_mkgeneric_line(line, GT_DIR); +} + +static int cpio_mkpipe_line(const char *line) +{ + return cpio_mkgeneric_line(line, GT_PIPE); +} + +static int cpio_mksock_line(const char *line) +{ + return cpio_mkgeneric_line(line, GT_SOCK); +} + +static int cpio_mknod(const char *name, unsigned int mode, + uid_t uid, gid_t gid, char dev_type, + unsigned int maj, unsigned int min) +{ + char s[256]; + + if (dev_type == 'b') + mode |= S_IFBLK; + else + mode |= S_IFCHR; + + if (name[0] == '/') + name++; + sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX" + "%08X%08X%08X%08X%08X%08X%08X", + do_csum ? "070702" : "070701", /* magic */ + ino++, /* ino */ + mode, /* mode */ + (long) uid, /* uid */ + (long) gid, /* gid */ + 1, /* nlink */ + (long) default_mtime, /* mtime */ + 0, /* filesize */ + 3, /* major */ + 1, /* minor */ + maj, /* rmajor */ + min, /* rminor */ + (unsigned)strlen(name) + 1,/* namesize */ + 0); /* chksum */ + push_hdr(s); + push_rest(name); + return 0; +} + +static int cpio_mknod_line(const char *line) +{ + char name[PATH_MAX + 1]; + unsigned int mode; + int uid; + int gid; + char dev_type; + unsigned int maj; + unsigned int min; + int rc = -1; + + if (7 != sscanf(line, "%" str(PATH_MAX) "s %o %d %d %c %u %u", + name, &mode, &uid, &gid, &dev_type, &maj, &min)) { + fprintf(stderr, "Unrecognized nod format '%s'", line); + goto fail; + } + rc = cpio_mknod(name, mode, uid, gid, dev_type, maj, min); + fail: + return rc; +} + +static int cpio_mkfile_csum(int fd, unsigned long size, uint32_t *csum) +{ + while (size) { + unsigned char filebuf[65536]; + ssize_t this_read; + size_t i, this_size = MIN(size, sizeof(filebuf)); + + this_read = read(fd, filebuf, this_size); + if (this_read <= 0 || this_read > this_size) + return -1; + + for (i = 0; i < this_read; i++) + *csum += filebuf[i]; + + size -= this_read; + } + /* seek back to the start for data segment I/O */ + if (lseek(fd, 0, SEEK_SET) < 0) + return -1; + + return 0; +} + +static int cpio_mkfile(const char *name, const char *location, + unsigned int mode, uid_t uid, gid_t gid, + unsigned int nlinks) +{ + char s[256]; + struct stat buf; + unsigned long size; + int file; + int retval; + int rc = -1; + int namesize; + unsigned int i; + uint32_t csum = 0; + + mode |= S_IFREG; + + file = open (location, O_RDONLY); + if (file < 0) { + fprintf (stderr, "File %s could not be opened for reading\n", location); + goto error; + } + + retval = fstat(file, &buf); + if (retval) { + fprintf(stderr, "File %s could not be stat()'ed\n", location); + goto error; + } + + if (buf.st_mtime > 0xffffffff) { + fprintf(stderr, "%s: Timestamp exceeds maximum cpio timestamp, clipping.\n", + location); + buf.st_mtime = 0xffffffff; + } + + if (buf.st_mtime < 0) { + fprintf(stderr, "%s: Timestamp negative, clipping.\n", + location); + buf.st_mtime = 0; + } + + if (buf.st_size > 0xffffffff) { + fprintf(stderr, "%s: Size exceeds maximum cpio file size\n", + location); + goto error; + } + + if (do_csum && cpio_mkfile_csum(file, buf.st_size, &csum) < 0) { + fprintf(stderr, "Failed to checksum file %s\n", location); + goto error; + } + + size = 0; + for (i = 1; i <= nlinks; i++) { + /* data goes on last link */ + if (i == nlinks) + size = buf.st_size; + + if (name[0] == '/') + name++; + namesize = strlen(name) + 1; + sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX" + "%08lX%08X%08X%08X%08X%08X%08X", + do_csum ? "070702" : "070701", /* magic */ + ino, /* ino */ + mode, /* mode */ + (long) uid, /* uid */ + (long) gid, /* gid */ + nlinks, /* nlink */ + (long) buf.st_mtime, /* mtime */ + size, /* filesize */ + 3, /* major */ + 1, /* minor */ + 0, /* rmajor */ + 0, /* rminor */ + namesize, /* namesize */ + size ? csum : 0); /* chksum */ + push_hdr(s); + push_string(name); + push_pad(); + + while (size) { + unsigned char filebuf[65536]; + ssize_t this_read; + size_t this_size = MIN(size, sizeof(filebuf)); + + this_read = read(file, filebuf, this_size); + if (this_read <= 0 || this_read > this_size) { + fprintf(stderr, "Can not read %s file\n", location); + goto error; + } + + if (fwrite(filebuf, this_read, 1, stdout) != 1) { + fprintf(stderr, "writing filebuf failed\n"); + goto error; + } + offset += this_read; + size -= this_read; + } + push_pad(); + + name += namesize; + } + ino++; + rc = 0; + +error: + if (file >= 0) + close(file); + return rc; +} + +static char *cpio_replace_env(char *new_location) +{ + char expanded[PATH_MAX + 1]; + char *start, *end, *var; + + while ((start = strstr(new_location, "${")) && + (end = strchr(start + 2, '}'))) { + *start = *end = 0; + var = getenv(start + 2); + snprintf(expanded, sizeof expanded, "%s%s%s", + new_location, var ? var : "", end + 1); + strcpy(new_location, expanded); + } + + return new_location; +} + +static int cpio_mkfile_line(const char *line) +{ + char name[PATH_MAX + 1]; + char *dname = NULL; /* malloc'ed buffer for hard links */ + char location[PATH_MAX + 1]; + unsigned int mode; + int uid; + int gid; + int nlinks = 1; + int end = 0, dname_len = 0; + int rc = -1; + + if (5 > sscanf(line, "%" str(PATH_MAX) "s %" str(PATH_MAX) + "s %o %d %d %n", + name, location, &mode, &uid, &gid, &end)) { + fprintf(stderr, "Unrecognized file format '%s'", line); + goto fail; + } + if (end && isgraph(line[end])) { + int len; + int nend; + + dname = malloc(strlen(line)); + if (!dname) { + fprintf (stderr, "out of memory (%d)\n", dname_len); + goto fail; + } + + dname_len = strlen(name) + 1; + memcpy(dname, name, dname_len); + + do { + nend = 0; + if (sscanf(line + end, "%" str(PATH_MAX) "s %n", + name, &nend) < 1) + break; + len = strlen(name) + 1; + memcpy(dname + dname_len, name, len); + dname_len += len; + nlinks++; + end += nend; + } while (isgraph(line[end])); + } else { + dname = name; + } + rc = cpio_mkfile(dname, cpio_replace_env(location), + mode, uid, gid, nlinks); + fail: + if (dname_len) free(dname); + return rc; +} + +static void usage(const char *prog) +{ + fprintf(stderr, "Usage:\n" + "\t%s [-t <timestamp>] [-c] <cpio_list>\n" + "\n" + "<cpio_list> is a file containing newline separated entries that\n" + "describe the files to be included in the initramfs archive:\n" + "\n" + "# a comment\n" + "file <name> <location> <mode> <uid> <gid> [<hard links>]\n" + "dir <name> <mode> <uid> <gid>\n" + "nod <name> <mode> <uid> <gid> <dev_type> <maj> <min>\n" + "slink <name> <target> <mode> <uid> <gid>\n" + "pipe <name> <mode> <uid> <gid>\n" + "sock <name> <mode> <uid> <gid>\n" + "\n" + "<name> name of the file/dir/nod/etc in the archive\n" + "<location> location of the file in the current filesystem\n" + " expands shell variables quoted with ${}\n" + "<target> link target\n" + "<mode> mode/permissions of the file\n" + "<uid> user id (0=root)\n" + "<gid> group id (0=root)\n" + "<dev_type> device type (b=block, c=character)\n" + "<maj> major number of nod\n" + "<min> minor number of nod\n" + "<hard links> space separated list of other links to file\n" + "\n" + "example:\n" + "# A simple initramfs\n" + "dir /dev 0755 0 0\n" + "nod /dev/console 0600 0 0 c 5 1\n" + "dir /root 0700 0 0\n" + "dir /sbin 0755 0 0\n" + "file /sbin/kinit /usr/src/klibc/kinit/kinit 0755 0 0\n" + "\n" + "<timestamp> is time in seconds since Epoch that will be used\n" + "as mtime for symlinks, special files and directories. The default\n" + "is to use the current time for these entries.\n" + "-c: calculate and store 32-bit checksums for file data.\n", + prog); +} + +static const struct file_handler file_handler_table[] = { + { + .type = "file", + .handler = cpio_mkfile_line, + }, { + .type = "nod", + .handler = cpio_mknod_line, + }, { + .type = "dir", + .handler = cpio_mkdir_line, + }, { + .type = "slink", + .handler = cpio_mkslink_line, + }, { + .type = "pipe", + .handler = cpio_mkpipe_line, + }, { + .type = "sock", + .handler = cpio_mksock_line, + }, { + .type = NULL, + .handler = NULL, + } +}; + +#define LINE_SIZE (2 * PATH_MAX + 50) + +int main (int argc, char *argv[]) +{ + FILE *cpio_list; + char line[LINE_SIZE]; + char *args, *type; + int ec = 0; + int line_nr = 0; + const char *filename; + + default_mtime = time(NULL); + while (1) { + int opt = getopt(argc, argv, "t:ch"); + char *invalid; + + if (opt == -1) + break; + switch (opt) { + case 't': + default_mtime = strtol(optarg, &invalid, 10); + if (!*optarg || *invalid) { + fprintf(stderr, "Invalid timestamp: %s\n", + optarg); + usage(argv[0]); + exit(1); + } + break; + case 'c': + do_csum = true; + break; + case 'h': + case '?': + usage(argv[0]); + exit(opt == 'h' ? 0 : 1); + } + } + + /* + * Timestamps after 2106-02-07 06:28:15 UTC have an ascii hex time_t + * representation that exceeds 8 chars and breaks the cpio header + * specification. Negative timestamps similarly exceed 8 chars. + */ + if (default_mtime > 0xffffffff || default_mtime < 0) { + fprintf(stderr, "ERROR: Timestamp out of range for cpio format\n"); + exit(1); + } + + if (argc - optind != 1) { + usage(argv[0]); + exit(1); + } + filename = argv[optind]; + if (!strcmp(filename, "-")) + cpio_list = stdin; + else if (!(cpio_list = fopen(filename, "r"))) { + fprintf(stderr, "ERROR: unable to open '%s': %s\n\n", + filename, strerror(errno)); + usage(argv[0]); + exit(1); + } + + while (fgets(line, LINE_SIZE, cpio_list)) { + int type_idx; + size_t slen = strlen(line); + + line_nr++; + + if ('#' == *line) { + /* comment - skip to next line */ + continue; + } + + if (! (type = strtok(line, " \t"))) { + fprintf(stderr, + "ERROR: incorrect format, could not locate file type line %d: '%s'\n", + line_nr, line); + ec = -1; + break; + } + + if ('\n' == *type) { + /* a blank line */ + continue; + } + + if (slen == strlen(type)) { + /* must be an empty line */ + continue; + } + + if (! (args = strtok(NULL, "\n"))) { + fprintf(stderr, + "ERROR: incorrect format, newline required line %d: '%s'\n", + line_nr, line); + ec = -1; + } + + for (type_idx = 0; file_handler_table[type_idx].type; type_idx++) { + int rc; + if (! strcmp(line, file_handler_table[type_idx].type)) { + if ((rc = file_handler_table[type_idx].handler(args))) { + ec = rc; + fprintf(stderr, " line %d\n", line_nr); + } + break; + } + } + + if (NULL == file_handler_table[type_idx].type) { + fprintf(stderr, "unknown file type line %d: '%s'\n", + line_nr, line); + } + } + if (ec == 0) + cpio_trailer(); + + exit(ec); +} |