diff options
Diffstat (limited to 'lib/tar/pax_header.c')
| -rw-r--r-- | lib/tar/pax_header.c | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/lib/tar/pax_header.c b/lib/tar/pax_header.c new file mode 100644 index 0000000..4eeabf5 --- /dev/null +++ b/lib/tar/pax_header.c @@ -0,0 +1,183 @@ +/* SPDX-License-Identifier: GPL-3.0-or-later */ +/* + * pax_header.c + * + * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at> + */ +#include "config.h" + +#include "internal.h" + +static tar_xattr_t *mkxattr(const char *key, size_t keylen, + const char *value, size_t valuelen) +{ + tar_xattr_t *xattr; + + xattr = calloc(1, sizeof(*xattr) + keylen + 1 + valuelen + 1); + if (xattr == NULL) + return NULL; + + xattr->key = xattr->data; + xattr->value = (sqfs_u8 *)xattr->data + keylen + 1; + xattr->value_len = valuelen; + memcpy(xattr->key, key, keylen); + memcpy(xattr->value, value, valuelen); + return xattr; +} + +int read_pax_header(FILE *fp, sqfs_u64 entsize, unsigned int *set_by_pax, + tar_header_decoded_t *out) +{ + char *buffer, *line, *key, *ptr, *value, *end; + sparse_map_t *sparse_last = NULL, *sparse; + sqfs_u64 field, offset = 0, num_bytes = 0; + tar_xattr_t *xattr; + long len; + + buffer = record_to_memory(fp, entsize); + if (buffer == NULL) + return -1; + + end = buffer + entsize; + + for (line = buffer; line < end; line += len) { + len = strtol(line, &ptr, 10); + if (ptr == line || !isspace(*ptr) || len <= 0) + goto fail_malformed; + + if (len > (end - line)) + goto fail_ov; + + line[len - 1] = '\0'; + + while (ptr < end && isspace(*ptr)) + ++ptr; + + if (ptr >= end || (ptr - line) >= len) + goto fail_malformed; + + if (!strncmp(ptr, "uid=", 4)) { + if (pax_read_decimal(ptr + 4, &field)) + goto fail; + out->sb.st_uid = field; + *set_by_pax |= PAX_UID; + } else if (!strncmp(ptr, "gid=", 4)) { + if (pax_read_decimal(ptr + 4, &field)) + goto fail; + out->sb.st_gid = field; + *set_by_pax |= PAX_GID; + } else if (!strncmp(ptr, "path=", 5)) { + free(out->name); + out->name = strdup(ptr + 5); + if (out->name == NULL) + goto fail_errno; + *set_by_pax |= PAX_NAME; + } else if (!strncmp(ptr, "size=", 5)) { + if (pax_read_decimal(ptr + 5, &out->record_size)) + goto fail; + *set_by_pax |= PAX_SIZE; + } else if (!strncmp(ptr, "linkpath=", 9)) { + free(out->link_target); + out->link_target = strdup(ptr + 9); + if (out->link_target == NULL) + goto fail_errno; + *set_by_pax |= PAX_SLINK_TARGET; + } else if (!strncmp(ptr, "mtime=", 6)) { + if (ptr[6] == '-') { + if (pax_read_decimal(ptr + 7, &field)) + goto fail; + out->mtime = -((sqfs_s64)field); + } else { + if (pax_read_decimal(ptr + 6, &field)) + goto fail; + out->mtime = field; + } + *set_by_pax |= PAX_MTIME; + } else if (!strncmp(ptr, "GNU.sparse.name=", 16)) { + free(out->name); + out->name = strdup(ptr + 16); + if (out->name == NULL) + goto fail_errno; + *set_by_pax |= PAX_NAME; + } else if (!strncmp(ptr, "GNU.sparse.map=", 15)) { + free_sparse_list(out->sparse); + sparse_last = NULL; + + out->sparse = read_sparse_map(ptr + 15); + if (out->sparse == NULL) + goto fail; + } else if (!strncmp(ptr, "GNU.sparse.size=", 16)) { + if (pax_read_decimal(ptr + 16, &out->actual_size)) + goto fail; + *set_by_pax |= PAX_SPARSE_SIZE; + } else if (!strncmp(ptr, "GNU.sparse.offset=", 18)) { + if (pax_read_decimal(ptr + 18, &offset)) + goto fail; + } else if (!strncmp(ptr, "GNU.sparse.numbytes=", 20)) { + if (pax_read_decimal(ptr + 20, &num_bytes)) + goto fail; + sparse = calloc(1, sizeof(*sparse)); + if (sparse == NULL) + goto fail_errno; + sparse->offset = offset; + sparse->count = num_bytes; + if (sparse_last == NULL) { + free_sparse_list(out->sparse); + out->sparse = sparse_last = sparse; + } else { + sparse_last->next = sparse; + sparse_last = sparse; + } + } else if (!strncmp(ptr, "SCHILY.xattr.", 13)) { + key = ptr + 13; + + ptr = strrchr(key, '='); + if (ptr == NULL || ptr == key) + continue; + + value = ptr + 1; + + xattr = mkxattr(key, ptr - key, + value, len - (value - line) - 1); + if (xattr == NULL) + goto fail_errno; + + xattr->next = out->xattr; + out->xattr = xattr; + } else if (!strncmp(ptr, "LIBARCHIVE.xattr.", 17)) { + key = ptr + 17; + + ptr = strrchr(key, '='); + if (ptr == NULL || ptr == key) + continue; + + value = ptr + 1; + + xattr = mkxattr(key, ptr - key, value, strlen(value)); + if (xattr == NULL) + goto fail_errno; + + urldecode(xattr->key); + xattr->value_len = base64_decode(xattr->value, value, + xattr->value_len); + + xattr->next = out->xattr; + out->xattr = xattr; + } + } + + free(buffer); + return 0; +fail_malformed: + fputs("Found a malformed PAX header.\n", stderr); + goto fail; +fail_ov: + fputs("Numeric overflow in PAX header.\n", stderr); + goto fail; +fail_errno: + perror("reading pax header"); + goto fail; +fail: + free(buffer); + return -1; +} |