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/* vi: set sw=4 ts=4: */
/*
* Mini rpm2cpio implementation for busybox
*
* Copyright (C) 2001 by Laurence Anderson
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
#include "libbb.h"
#include "unarchive.h"
#define RPM_MAGIC "\355\253\356\333"
#define RPM_HEADER_MAGIC "\216\255\350"
struct rpm_lead {
unsigned char magic[4];
uint8_t major, minor;
uint16_t type;
uint16_t archnum;
char name[66];
uint16_t osnum;
uint16_t signature_type;
char reserved[16];
};
struct rpm_header {
char magic[3]; /* 3 byte magic: 0x8e 0xad 0xe8 */
uint8_t version; /* 1 byte version number */
uint32_t reserved; /* 4 bytes reserved */
uint32_t entries; /* Number of entries in header (4 bytes) */
uint32_t size; /* Size of store (4 bytes) */
};
static void skip_header(int rpm_fd)
{
struct rpm_header header;
xread(rpm_fd, &header, sizeof(struct rpm_header));
if (strncmp((char *) &header.magic, RPM_HEADER_MAGIC, 3) != 0) {
bb_error_msg_and_die("invalid RPM header magic"); /* Invalid magic */
}
if (header.version != 1) {
bb_error_msg_and_die("unsupported RPM header version"); /* This program only supports v1 headers */
}
header.entries = ntohl(header.entries);
header.size = ntohl(header.size);
lseek (rpm_fd, 16 * header.entries, SEEK_CUR); /* Seek past index entries */
lseek (rpm_fd, header.size, SEEK_CUR); /* Seek past store */
}
/* No getopt required */
int rpm2cpio_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int rpm2cpio_main(int argc, char **argv)
{
struct rpm_lead lead;
int rpm_fd;
unsigned char magic[2];
if (argc == 1) {
rpm_fd = STDIN_FILENO;
} else {
rpm_fd = xopen(argv[1], O_RDONLY);
}
xread(rpm_fd, &lead, sizeof(struct rpm_lead));
if (strncmp((char *) &lead.magic, RPM_MAGIC, 4) != 0) {
bb_error_msg_and_die("invalid RPM magic"); /* Just check the magic, the rest is irrelevant */
}
/* Skip the signature header */
skip_header(rpm_fd);
lseek(rpm_fd, (8 - (lseek(rpm_fd, 0, SEEK_CUR) % 8)) % 8, SEEK_CUR);
/* Skip the main header */
skip_header(rpm_fd);
xread(rpm_fd, &magic, 2);
if ((magic[0] != 0x1f) || (magic[1] != 0x8b)) {
bb_error_msg_and_die("invalid gzip magic");
}
if (unpack_gz_stream(rpm_fd, STDOUT_FILENO) < 0) {
bb_error_msg("error inflating");
}
close(rpm_fd);
return 0;
}
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