def genl_ctrl_probe_by_name(sk, name): """Look up generic Netlink family by family name querying the kernel directly. https://github.com/thom311/libnl/blob/libnl3_2_25/lib/genl/ctrl.c#L237 Directly query's the kernel for a given family name. Note: This API call differs from genl_ctrl_search_by_name in that it queries the kernel directly, allowing for module autoload to take place to resolve the family request. Using an nl_cache prevents that operation. Positional arguments: sk -- Generic Netlink socket (nl_sock class instance). name -- family name (bytes). Returns: Generic Netlink family `genl_family` class instance or None if no match was found. """ ret = genl_family_alloc() if not ret: return None genl_family_set_name(ret, name) msg = nlmsg_alloc() orig = nl_socket_get_cb(sk) cb = nl_cb_clone(orig) genlmsg_put(msg, NL_AUTO_PORT, NL_AUTO_SEQ, GENL_ID_CTRL, 0, 0, CTRL_CMD_GETFAMILY, 1) nla_put_string(msg, CTRL_ATTR_FAMILY_NAME, name) nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, probe_response, ret) if nl_send_auto(sk, msg) < 0: return None if nl_recvmsgs(sk, cb) < 0: return None if wait_for_ack( sk ) < 0: # If search was successful, request may be ACKed after data. return None if genl_family_get_id(ret) != 0: return ret
def genl_ctrl_probe_by_name(sk, name): """Look up generic Netlink family by family name querying the kernel directly. https://github.com/thom311/libnl/blob/libnl3_2_25/lib/genl/ctrl.c#L237 Directly query's the kernel for a given family name. Note: This API call differs from genl_ctrl_search_by_name in that it queries the kernel directly, allowing for module autoload to take place to resolve the family request. Using an nl_cache prevents that operation. Positional arguments: sk -- Generic Netlink socket (nl_sock class instance). name -- family name (bytes). Returns: Generic Netlink family `genl_family` class instance or None if no match was found. """ ret = genl_family_alloc() if not ret: return None genl_family_set_name(ret, name) msg = nlmsg_alloc() orig = nl_socket_get_cb(sk) cb = nl_cb_clone(orig) genlmsg_put(msg, NL_AUTO_PORT, NL_AUTO_SEQ, GENL_ID_CTRL, 0, 0, CTRL_CMD_GETFAMILY, 1) nla_put_string(msg, CTRL_ATTR_FAMILY_NAME, name) nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, probe_response, ret) if nl_send_auto(sk, msg) < 0: return None if nl_recvmsgs(sk, cb) < 0: return None if wait_for_ack(sk) < 0: # If search was successful, request may be ACKed after data. return None if genl_family_get_id(ret) != 0: return ret
def test_nl_cache_ops_associate_safe(): r"""C code to test against. // gcc a.c $(pkg-config --cflags --libs libnl-genl-3.0) && ./a.out #include <netlink/genl/family.h> struct nl_sock { struct sockaddr_nl s_local; struct sockaddr_nl s_peer; int s_fd; int s_proto; unsigned int s_seq_next; unsigned int s_seq_expect; int s_flags; struct nl_cb *s_cb; size_t s_bufsize; }; struct nl_cache_ops { char *co_name; int co_hdrsize; int co_protocol; int co_hash_size; unsigned int co_flags; unsigned int co_refcnt; struct nl_af_group *co_groups; int (*co_request_update)(struct nl_cache*, struct nl_sock*); int (*co_msg_parser)(struct nl_cache_ops*, struct sockaddr_nl*, struct nlmsghdr*, struct nl_parser_param*); int (*co_event_filter)(struct nl_cache*, struct nl_object *obj); int (*co_include_event)(struct nl_cache *cache, struct nl_object *obj, change_func_t change_cb, void *data); void (*reserved_1)(void); void (*reserved_2)(void); void (*reserved_3)(void); void (*reserved_4)(void); void (*reserved_5)(void); void (*reserved_6)(void); void (*reserved_7)(void); void (*reserved_8)(void); struct nl_object_ops *co_obj_ops; }; struct nl_object_ops { char *oo_name; size_t oo_size; uint32_t oo_id_attrs; }; struct nl_msgtype { int mt_id; int mt_act; char *mt_name; }; static int callback(struct nl_sock *sk, struct nl_msg *msg) { struct nlmsghdr *nlh = nlmsg_hdr(msg); printf("%d == nlh.nlmsg_len\n", nlh->nlmsg_len); printf("%d == nlh.nlmsg_type\n", nlh->nlmsg_type); printf("%d == nlh.nlmsg_flags\n", nlh->nlmsg_flags); struct nl_cache_ops *ops = nl_cache_ops_associate_safe(NETLINK_GENERIC, nlh->nlmsg_type); printf("'%s' == ops.co_name\n", ops->co_name); printf("%d == ops.co_hdrsize\n", ops->co_hdrsize); printf("%d == ops.co_protocol\n", ops->co_protocol); printf("%d == ops.co_hash_size\n", ops->co_hash_size); printf("%d == ops.co_flags\n", ops->co_flags); printf("'%s' == ops.co_obj_ops.oo_name\n", ops->co_obj_ops->oo_name); printf("%d == ops.co_obj_ops.oo_size\n", ops->co_obj_ops->oo_size); printf("%d == ops.co_obj_ops.oo_id_attrs\n", ops->co_obj_ops->oo_id_attrs); printf("%d == nlmsg_attrlen(nlh, ops.co_hdrsize)\n", nlmsg_attrlen(nlh, ops->co_hdrsize)); struct nl_msgtype *mt = nl_msgtype_lookup(ops, nlh->nlmsg_type); printf("%d == mt.mt_id\n", mt->mt_id); printf("%d == mt.mt_act\n", mt->mt_act); printf("'%s' == mt.mt_name\n", mt->mt_name); return NL_STOP; } int main() { struct nl_sock *sk = nl_socket_alloc(); nl_cb_overwrite_send(sk->s_cb, callback); struct genl_family *ret = genl_family_alloc(); genl_family_set_name(ret, "nl80211"); struct nl_msg *msg = nlmsg_alloc(); genlmsg_put(msg, NL_AUTO_PORT, NL_AUTO_SEQ, GENL_ID_CTRL, 0, 0, CTRL_CMD_GETFAMILY, 1); printf("%d == nl_send_auto(sk, msg)\n", nl_send_auto(sk, msg)); return 0; } // Expected output: // 20 == nlh.nlmsg_len // 16 == nlh.nlmsg_type // 5 == nlh.nlmsg_flags // 'genl/family' == ops.co_name // 4 == ops.co_hdrsize // 16 == ops.co_protocol // 0 == ops.co_hash_size // 0 == ops.co_flags // 'genl/family' == ops.co_obj_ops.oo_name // 80 == ops.co_obj_ops.oo_size // 1 == ops.co_obj_ops.oo_id_attrs // 0 == nlmsg_attrlen(nlh, ops.co_hdrsize) // 16 == mt.mt_id // 0 == mt.mt_act // 'nlctrl' == mt.mt_name // 2 == nl_send_auto(sk, msg) """ called = list() def callback(_, msg_): nlh = nlmsg_hdr(msg_) assert 20 == nlh.nlmsg_len assert 16 == nlh.nlmsg_type assert 5 == nlh.nlmsg_flags ops = nl_cache_ops_associate_safe(NETLINK_GENERIC, nlh.nlmsg_type) assert 'genl/family' == ops.co_name assert 4 == ops.co_hdrsize assert 16 == ops.co_protocol assert 0 == ops.co_hash_size assert 0 == ops.co_flags assert 'genl/family' == ops.co_obj_ops.oo_name assert 80 == ops.co_obj_ops.oo_size assert 1 == ops.co_obj_ops.oo_id_attrs assert 0 == nlmsg_attrlen(nlh, ops.co_hdrsize) mt = nl_msgtype_lookup(ops, nlh.nlmsg_type) assert 16 == mt.mt_id assert 0 == mt.mt_act assert 'nlctrl' == mt.mt_name called.append(True) return NL_STOP sk = nl_socket_alloc() nl_cb_overwrite_send(sk.s_cb, callback) ret = genl_family_alloc() genl_family_set_name(ret, 'nl80211') msg = nlmsg_alloc() genlmsg_put(msg, NL_AUTO_PORT, NL_AUTO_SEQ, GENL_ID_CTRL, 0, 0, CTRL_CMD_GETFAMILY, 1) assert 2 == nl_send_auto(sk, msg) assert [True] == called
def test_ctrl_cmd_getfamily_hex_dump(log): r"""C code to test against. // gcc a.c $(pkg-config --cflags --libs libnl-genl-3.0) && NLDBG=4 ./a.out #include <netlink/msg.h> struct nl_sock { struct sockaddr_nl s_local; struct sockaddr_nl s_peer; int s_fd; int s_proto; unsigned int s_seq_next; unsigned int s_seq_expect; int s_flags; struct nl_cb *s_cb; size_t s_bufsize; }; static void prefix_line(FILE *ofd, int prefix) { int i; for (i = 0; i < prefix; i++) fprintf(ofd, " "); } static inline void dump_hex(FILE *ofd, char *start, int len, int prefix) { int i, a, c, limit; char ascii[21] = {0}; limit = 16 - (prefix * 2); prefix_line(ofd, prefix); fprintf(ofd, " "); for (i = 0, a = 0, c = 0; i < len; i++) { int v = *(uint8_t *) (start + i); fprintf(ofd, "%02x ", v); ascii[a++] = isprint(v) ? v : '.'; if (++c >= limit) { fprintf(ofd, "%s\n", ascii); if (i < (len - 1)) { prefix_line(ofd, prefix); fprintf(ofd, " "); } a = c = 0; memset(ascii, 0, sizeof(ascii)); } } if (c != 0) { for (i = 0; i < (limit - c); i++) fprintf(ofd, " "); fprintf(ofd, "%s\n", ascii); } } struct ucred { pid_t pid; uid_t uid; gid_t gid; }; struct nl_msg { int nm_protocol; int nm_flags; struct sockaddr_nl nm_src; struct sockaddr_nl nm_dst; struct ucred nm_creds; struct nlmsghdr *nm_nlh; size_t nm_size; int nm_refcnt; }; static int callback_send(struct nl_sock *sk, struct nl_msg *msg) { printf("%d == msg.nm_protocol\n", msg->nm_protocol); printf("%d == msg.nm_flags\n", msg->nm_flags); printf("%d == msg.nm_src.nl_family\n", msg->nm_src.nl_family); printf("%d == msg.nm_src.nl_pid\n", msg->nm_src.nl_pid); printf("%d == msg.nm_src.nl_groups\n", msg->nm_src.nl_groups); printf("%d == msg.nm_dst.nl_family\n", msg->nm_dst.nl_family); printf("%d == msg.nm_dst.nl_pid\n", msg->nm_dst.nl_pid); printf("%d == msg.nm_dst.nl_groups\n", msg->nm_dst.nl_groups); printf("%d == msg.nm_creds.pid\n", msg->nm_creds.pid); printf("%d == msg.nm_creds.uid\n", msg->nm_creds.uid); printf("%d == msg.nm_creds.gid\n", msg->nm_creds.gid); printf("%d == msg.nm_nlh.nlmsg_type\n", msg->nm_nlh->nlmsg_type); printf("%d == msg.nm_nlh.nlmsg_flags\n", msg->nm_nlh->nlmsg_flags); printf("%d == msg.nm_nlh.nlmsg_pid\n", msg->nm_nlh->nlmsg_pid); printf("%d == msg.nm_size\n", msg->nm_size); printf("%d == msg.nm_refcnt\n", msg->nm_refcnt); struct iovec iov = { .iov_base = (void *) nlmsg_hdr(msg), .iov_len = nlmsg_hdr(msg)->nlmsg_len, }; dump_hex(stdout, iov.iov_base, iov.iov_len, 0); return nl_send_iovec(sk, msg, &iov, 1); } static int callback_recv(struct nl_sock *sk, struct sockaddr_nl *nla, unsigned char **buf, struct ucred **creds) { int n = nl_recv(sk, nla, buf, creds); dump_hex(stdout, (void *) *buf, n, 0); return n; } static int callback_recv_msg(struct nl_msg *msg, void *arg) { printf("%d == msg.nm_protocol\n", msg->nm_protocol); printf("%d == msg.nm_flags\n", msg->nm_flags); printf("%d == msg.nm_src.nl_family\n", msg->nm_src.nl_family); printf("%d == msg.nm_src.nl_pid\n", msg->nm_src.nl_pid); printf("%d == msg.nm_src.nl_groups\n", msg->nm_src.nl_groups); printf("%d == msg.nm_dst.nl_family\n", msg->nm_dst.nl_family); printf("%d == msg.nm_dst.nl_pid\n", msg->nm_dst.nl_pid); printf("%d == msg.nm_dst.nl_groups\n", msg->nm_dst.nl_groups); printf("%d == msg.nm_creds.pid\n", msg->nm_creds.pid); printf("%d == msg.nm_creds.uid\n", msg->nm_creds.uid); printf("%d == msg.nm_creds.gid\n", msg->nm_creds.gid); printf("%d == msg.nm_nlh.nlmsg_type\n", msg->nm_nlh->nlmsg_type); printf("%d == msg.nm_nlh.nlmsg_flags\n", msg->nm_nlh->nlmsg_flags); printf("%d == msg.nm_nlh.nlmsg_pid\n", msg->nm_nlh->nlmsg_pid); printf("%d == msg.nm_size\n", msg->nm_size); printf("%d == msg.nm_refcnt\n", msg->nm_refcnt); dump_hex(stdout, (char *) msg->nm_nlh, nlmsg_datalen(msg->nm_nlh), 0); return NL_OK; } int main() { struct nl_sock *sk = nl_socket_alloc(); nl_cb_overwrite_send(sk->s_cb, callback_send); nl_cb_overwrite_recv(sk->s_cb, callback_recv); printf("%d == genl_connect(sk)\n", genl_connect(sk)); struct genl_family *ret = (struct genl_family *) genl_family_alloc(); genl_family_set_name(ret, "nl80211"); struct nl_msg *msg = nlmsg_alloc(); genlmsg_put(msg, NL_AUTO_PORT, NL_AUTO_SEQ, GENL_ID_CTRL, 0, 0, CTRL_CMD_GETFAMILY, 1); nla_put_string(msg, CTRL_ATTR_FAMILY_NAME, "nl80211"); nl_socket_modify_cb(sk, NL_CB_VALID, NL_CB_CUSTOM, callback_recv_msg, NULL); printf("%d == nl_send_auto(sk, msg)\n", nl_send_auto(sk, msg)); printf("%d == nl_recvmsgs_default(sk)\n", nl_recvmsgs_default(sk)); nl_socket_free(sk); return 0; } // Expected output (trimmed): // nl_cache_mngt_register: Registered cache operations genl/family // 0 == genl_connect(sk) // nl_object_alloc: Allocated new object 0x2b50b8 // __nlmsg_alloc: msg 0x2b5110: Allocated new message, maxlen=4096 // nlmsg_put: msg 0x2b5110: Added netlink header type=16, flags=0, pid=0, seq=0 // nlmsg_reserve: msg 0x2b5110: Reserved 4 (4) bytes, pad=4, nlmsg_len=20 // genlmsg_put: msg 0x2b5110: Added generic netlink header cmd=3 version=1 // nla_reserve: msg 0x2b5110: attr <0x2b5164> 2: Reserved 12 (8) bytes at offset +4 nlmsg_len=32 // nla_put: msg 0x2b5110: attr <0x2b5164> 2: Wrote 8 bytes at offset +4 // 16 == msg.nm_protocol // 0 == msg.nm_flags // 0 == msg.nm_src.nl_family // 0 == msg.nm_src.nl_pid // 0 == msg.nm_src.nl_groups // 0 == msg.nm_dst.nl_family // 0 == msg.nm_dst.nl_pid // 0 == msg.nm_dst.nl_groups // 0 == msg.nm_creds.pid // 0 == msg.nm_creds.uid // 0 == msg.nm_creds.gid // 16 == msg.nm_nlh.nlmsg_type // 5 == msg.nm_nlh.nlmsg_flags // 14272 == msg.nm_nlh.nlmsg_pid // 4096 == msg.nm_size // 1 == msg.nm_refcnt // 20 00 00 00 10 00 05 00 af aa f6 54 c0 37 00 00 ..........T.7.. // 03 01 00 00 0c 00 02 00 6e 6c 38 30 32 31 31 00 ........nl80211. // nl_sendmsg: sent 32 bytes // 32 == nl_send_auto(sk, msg) // recvmsgs: Attempting to read from 0x2b5080 // 2c 07 00 00 10 00 00 00 af aa f6 54 c0 37 00 00 ,..........T.7.. // 01 02 00 00 0c 00 02 00 6e 6c 38 30 32 31 31 00 ........nl80211. // 06 00 01 00 16 00 00 00 08 00 03 00 01 00 00 00 ................ // 08 00 04 00 00 00 00 00 08 00 05 00 d5 00 00 00 ................ // 6c 06 06 00 14 00 01 00 08 00 01 00 01 00 00 00 l............... // 08 00 02 00 0e 00 00 00 14 00 02 00 08 00 01 00 ................ // <trimmed> // 63 6f 6e 66 69 67 00 00 18 00 02 00 08 00 02 00 config.......... // 04 00 00 00 09 00 01 00 73 63 61 6e 00 00 00 00 ........scan.... // 1c 00 03 00 08 00 02 00 05 00 00 00 0f 00 01 00 ................ // 72 65 67 75 6c 61 74 6f 72 79 00 00 18 00 04 00 regulatory...... // 08 00 02 00 06 00 00 00 09 00 01 00 6d 6c 6d 65 ............mlme // 00 00 00 00 18 00 05 00 08 00 02 00 07 00 00 00 ................ // 0b 00 01 00 76 65 6e 64 6f 72 00 00 ....vendor.. // recvmsgs: recvmsgs(0x2b5080): Read 1836 bytes // recvmsgs: recvmsgs(0x2b5080): Processing valid message... // __nlmsg_alloc: msg 0x2ba160: Allocated new message, maxlen=1836 // 16 == msg.nm_protocol // 0 == msg.nm_flags // 16 == msg.nm_src.nl_family // 0 == msg.nm_src.nl_pid // 0 == msg.nm_src.nl_groups // 0 == msg.nm_dst.nl_family // 0 == msg.nm_dst.nl_pid // 0 == msg.nm_dst.nl_groups // 0 == msg.nm_creds.pid // 0 == msg.nm_creds.uid // 0 == msg.nm_creds.gid // 16 == msg.nm_nlh.nlmsg_type // 0 == msg.nm_nlh.nlmsg_flags // 14272 == msg.nm_nlh.nlmsg_pid // 1836 == msg.nm_size // 1 == msg.nm_refcnt // 2c 07 00 00 10 00 00 00 af aa f6 54 c0 37 00 00 ,..........T.7.. // 01 02 00 00 0c 00 02 00 6e 6c 38 30 32 31 31 00 ........nl80211. // 06 00 01 00 16 00 00 00 08 00 03 00 01 00 00 00 ................ // 08 00 04 00 00 00 00 00 08 00 05 00 d5 00 00 00 ................ // 6c 06 06 00 14 00 01 00 08 00 01 00 01 00 00 00 l............... // 08 00 02 00 0e 00 00 00 14 00 02 00 08 00 01 00 ................ // <trimmed> // 63 6f 6e 66 69 67 00 00 18 00 02 00 08 00 02 00 config.......... // 04 00 00 00 09 00 01 00 73 63 61 6e 00 00 00 00 ........scan.... // 1c 00 03 00 08 00 02 00 05 00 00 00 0f 00 01 00 ................ // 72 65 67 75 6c 61 74 6f 72 79 00 00 18 00 04 00 regulatory...... // 08 00 02 00 06 00 00 00 09 00 01 00 6d 6c 6d 65 ............mlme // 00 00 00 00 18 00 05 00 08 00 02 00 ............ // nlmsg_free: Returned message reference 0x2ba160, 0 remaining // nlmsg_free: msg 0x2ba160: Freed // 0 == nl_recvmsgs_default(sk) // nl_cache_mngt_unregister: Unregistered cache operations genl/family """ def callback_send(sk, msg): assert 16 == msg.nm_protocol assert 0 == msg.nm_flags assert 0 == msg.nm_src.nl_family assert 0 == msg.nm_src.nl_pid assert 0 == msg.nm_src.nl_groups assert 0 == msg.nm_dst.nl_family assert 0 == msg.nm_dst.nl_pid assert 0 == msg.nm_dst.nl_groups assert msg.nm_creds is None assert 16 == msg.nm_nlh.nlmsg_type assert 5 == msg.nm_nlh.nlmsg_flags assert 100 < msg.nm_nlh.nlmsg_pid assert 1 == msg.nm_refcnt hdr = nlmsg_hdr(msg) iov = hdr.bytearray[:hdr.nlmsg_len] dump_hex(logging.getLogger().debug, iov, len(iov), 0) return nl_send_iovec(sk, msg, iov, 1) def callback_recv(sk, nla, buf, creds): n = nl_recv(sk, nla, buf, creds) dump_hex(logging.getLogger().debug, buf, len(buf), 0) return n def callback_recv_msg(msg, _): assert 16 == msg.nm_protocol assert 0 == msg.nm_flags assert 16 == msg.nm_src.nl_family assert 0 == msg.nm_src.nl_pid assert 0 == msg.nm_src.nl_groups assert 0 == msg.nm_dst.nl_family assert 0 == msg.nm_dst.nl_pid assert 0 == msg.nm_dst.nl_groups assert msg.nm_creds is None assert 16 == msg.nm_nlh.nlmsg_type assert 0 == msg.nm_nlh.nlmsg_flags assert 100 < msg.nm_nlh.nlmsg_pid assert 1000 < msg.nm_size assert 1 == msg.nm_refcnt dump_hex(logging.getLogger().debug, msg.nm_nlh.bytearray, nlmsg_datalen(msg.nm_nlh), 0) return NL_OK del log[:] sk_main = nl_socket_alloc() nl_cb_overwrite_send(sk_main.s_cb, callback_send) nl_cb_overwrite_recv(sk_main.s_cb, callback_recv) genl_connect(sk_main) ret = genl_family_alloc() genl_family_set_name(ret, b'nl80211') msg_main = nlmsg_alloc() genlmsg_put(msg_main, NL_AUTO_PORT, NL_AUTO_SEQ, GENL_ID_CTRL, 0, 0, CTRL_CMD_GETFAMILY, 1) nla_put_string(msg_main, CTRL_ATTR_FAMILY_NAME, b'nl80211') nl_socket_modify_cb(sk_main, NL_CB_VALID, NL_CB_CUSTOM, callback_recv_msg, None) assert 32 == nl_send_auto(sk_main, msg_main) assert 0 == nl_recvmsgs_default(sk_main) nl_socket_free(sk_main) assert match('nl_object_alloc: Allocated new object 0x[a-f0-9]+', log, True) assert match( 'nlmsg_alloc: msg 0x[a-f0-9]+: Allocated new message, maxlen=4096', log, True) assert match( 'nlmsg_put: msg 0x[a-f0-9]+: Added netlink header type=16, flags=0, pid=0, seq=0', log, True) assert match( 'nlmsg_reserve: msg 0x[a-f0-9]+: Reserved 4 \(4\) bytes, pad=4, nlmsg_len=20', log, True) assert match( 'genlmsg_put: msg 0x[a-f0-9]+: Added generic netlink header cmd=3 version=1', log, True) assert match( 'nla_reserve: msg 0x[a-f0-9]+: attr <0x[a-f0-9]+> 2: Reserved 12 \(8\) bytes at offset \+4 nlmsg_len=32', log, True) assert match( 'nla_put: msg 0x[a-f0-9]+: attr <0x[a-f0-9]+> 2: Wrote 8 bytes at offset \+4', log, True) assert match( 'dump_hex: 20 00 00 00 10 00 05 00 .. .. .. .. .. .. 00 00 ...............', log, True) assert match( 'dump_hex: 03 01 00 00 0c 00 02 00 6e 6c 38 30 32 31 31 00 ........nl80211.', log) assert match('nl_sendmsg: sent 32 bytes', log) assert match('recvmsgs: Attempting to read from 0x[a-f0-9]+', log, True) assert match( 'dump_hex: .. .. 00 00 10 00 00 00 .. .. .. .. .. .. 00 00 ................', log, True) assert match( 'dump_hex: 01 02 00 00 0c 00 02 00 6e 6c 38 30 32 31 31 00 ........nl80211.', log) assert match( 'dump_hex: 06 00 01 00 .. 00 00 00 08 00 03 00 01 00 00 00 ................', log, True) assert match( 'dump_hex: 08 00 04 00 00 00 00 00 08 00 05 00 .. 00 00 00 ................', log, True) for i in range(len(log)): if re.match(r'recvmsgs: recvmsgs\(0x[a-f0-9]+\): Read \d{4,} bytes', log[i]): log = log[i:] break assert match('recvmsgs: recvmsgs\(0x[a-f0-9]+\): Read \d{3,} bytes', log, True) assert match( 'recvmsgs: recvmsgs\(0x[a-f0-9]+\): Processing valid message...', log, True) assert match( 'nlmsg_alloc: msg 0x[a-f0-9]+: Allocated new message, maxlen=\d{3,}', log, True) assert match( 'dump_hex: .. .. 00 00 10 00 00 00 .. .. .. .. .. .. 00 00 ................', log, True) assert match( 'dump_hex: 01 02 00 00 0c 00 02 00 6e 6c 38 30 32 31 31 00 ........nl80211.', log) assert match( 'dump_hex: 06 00 01 00 .. 00 00 00 08 00 03 00 01 00 00 00 ................', log, True) assert match( 'dump_hex: 08 00 04 00 00 00 00 00 08 00 05 00 .. 00 00 00 ................', log, True) while log and log[0].startswith('dump_hex:'): log.pop(0) assert not log
def test_ctrl_cmd_getfamily_hex_dump(log): r"""C code to test against. // gcc a.c $(pkg-config --cflags --libs libnl-genl-3.0) && NLDBG=4 ./a.out #include <netlink/msg.h> struct nl_sock { struct sockaddr_nl s_local; struct sockaddr_nl s_peer; int s_fd; int s_proto; unsigned int s_seq_next; unsigned int s_seq_expect; int s_flags; struct nl_cb *s_cb; size_t s_bufsize; }; static void prefix_line(FILE *ofd, int prefix) { int i; for (i = 0; i < prefix; i++) fprintf(ofd, " "); } static inline void dump_hex(FILE *ofd, char *start, int len, int prefix) { int i, a, c, limit; char ascii[21] = {0}; limit = 16 - (prefix * 2); prefix_line(ofd, prefix); fprintf(ofd, " "); for (i = 0, a = 0, c = 0; i < len; i++) { int v = *(uint8_t *) (start + i); fprintf(ofd, "%02x ", v); ascii[a++] = isprint(v) ? v : '.'; if (++c >= limit) { fprintf(ofd, "%s\n", ascii); if (i < (len - 1)) { prefix_line(ofd, prefix); fprintf(ofd, " "); } a = c = 0; memset(ascii, 0, sizeof(ascii)); } } if (c != 0) { for (i = 0; i < (limit - c); i++) fprintf(ofd, " "); fprintf(ofd, "%s\n", ascii); } } struct ucred { pid_t pid; uid_t uid; gid_t gid; }; struct nl_msg { int nm_protocol; int nm_flags; struct sockaddr_nl nm_src; struct sockaddr_nl nm_dst; struct ucred nm_creds; struct nlmsghdr *nm_nlh; size_t nm_size; int nm_refcnt; }; static int callback_send(struct nl_sock *sk, struct nl_msg *msg) { printf("%d == msg.nm_protocol\n", msg->nm_protocol); printf("%d == msg.nm_flags\n", msg->nm_flags); printf("%d == msg.nm_src.nl_family\n", msg->nm_src.nl_family); printf("%d == msg.nm_src.nl_pid\n", msg->nm_src.nl_pid); printf("%d == msg.nm_src.nl_groups\n", msg->nm_src.nl_groups); printf("%d == msg.nm_dst.nl_family\n", msg->nm_dst.nl_family); printf("%d == msg.nm_dst.nl_pid\n", msg->nm_dst.nl_pid); printf("%d == msg.nm_dst.nl_groups\n", msg->nm_dst.nl_groups); printf("%d == msg.nm_creds.pid\n", msg->nm_creds.pid); printf("%d == msg.nm_creds.uid\n", msg->nm_creds.uid); printf("%d == msg.nm_creds.gid\n", msg->nm_creds.gid); printf("%d == msg.nm_nlh.nlmsg_type\n", msg->nm_nlh->nlmsg_type); printf("%d == msg.nm_nlh.nlmsg_flags\n", msg->nm_nlh->nlmsg_flags); printf("%d == msg.nm_nlh.nlmsg_pid\n", msg->nm_nlh->nlmsg_pid); printf("%d == msg.nm_size\n", msg->nm_size); printf("%d == msg.nm_refcnt\n", msg->nm_refcnt); struct iovec iov = { .iov_base = (void *) nlmsg_hdr(msg), .iov_len = nlmsg_hdr(msg)->nlmsg_len, }; dump_hex(stdout, iov.iov_base, iov.iov_len, 0); return nl_send_iovec(sk, msg, &iov, 1); } static int callback_recv(struct nl_sock *sk, struct sockaddr_nl *nla, unsigned char **buf, struct ucred **creds) { int n = nl_recv(sk, nla, buf, creds); dump_hex(stdout, (void *) *buf, n, 0); return n; } static int callback_recv_msg(struct nl_msg *msg, void *arg) { printf("%d == msg.nm_protocol\n", msg->nm_protocol); printf("%d == msg.nm_flags\n", msg->nm_flags); printf("%d == msg.nm_src.nl_family\n", msg->nm_src.nl_family); printf("%d == msg.nm_src.nl_pid\n", msg->nm_src.nl_pid); printf("%d == msg.nm_src.nl_groups\n", msg->nm_src.nl_groups); printf("%d == msg.nm_dst.nl_family\n", msg->nm_dst.nl_family); printf("%d == msg.nm_dst.nl_pid\n", msg->nm_dst.nl_pid); printf("%d == msg.nm_dst.nl_groups\n", msg->nm_dst.nl_groups); printf("%d == msg.nm_creds.pid\n", msg->nm_creds.pid); printf("%d == msg.nm_creds.uid\n", msg->nm_creds.uid); printf("%d == msg.nm_creds.gid\n", msg->nm_creds.gid); printf("%d == msg.nm_nlh.nlmsg_type\n", msg->nm_nlh->nlmsg_type); printf("%d == msg.nm_nlh.nlmsg_flags\n", msg->nm_nlh->nlmsg_flags); printf("%d == msg.nm_nlh.nlmsg_pid\n", msg->nm_nlh->nlmsg_pid); printf("%d == msg.nm_size\n", msg->nm_size); printf("%d == msg.nm_refcnt\n", msg->nm_refcnt); dump_hex(stdout, (char *) msg->nm_nlh, nlmsg_datalen(msg->nm_nlh), 0); return NL_OK; } int main() { struct nl_sock *sk = nl_socket_alloc(); nl_cb_overwrite_send(sk->s_cb, callback_send); nl_cb_overwrite_recv(sk->s_cb, callback_recv); printf("%d == genl_connect(sk)\n", genl_connect(sk)); struct genl_family *ret = (struct genl_family *) genl_family_alloc(); genl_family_set_name(ret, "nl80211"); struct nl_msg *msg = nlmsg_alloc(); genlmsg_put(msg, NL_AUTO_PORT, NL_AUTO_SEQ, GENL_ID_CTRL, 0, 0, CTRL_CMD_GETFAMILY, 1); nla_put_string(msg, CTRL_ATTR_FAMILY_NAME, "nl80211"); nl_socket_modify_cb(sk, NL_CB_VALID, NL_CB_CUSTOM, callback_recv_msg, NULL); printf("%d == nl_send_auto(sk, msg)\n", nl_send_auto(sk, msg)); printf("%d == nl_recvmsgs_default(sk)\n", nl_recvmsgs_default(sk)); nl_socket_free(sk); return 0; } // Expected output (trimmed): // nl_cache_mngt_register: Registered cache operations genl/family // 0 == genl_connect(sk) // nl_object_alloc: Allocated new object 0x2b50b8 // __nlmsg_alloc: msg 0x2b5110: Allocated new message, maxlen=4096 // nlmsg_put: msg 0x2b5110: Added netlink header type=16, flags=0, pid=0, seq=0 // nlmsg_reserve: msg 0x2b5110: Reserved 4 (4) bytes, pad=4, nlmsg_len=20 // genlmsg_put: msg 0x2b5110: Added generic netlink header cmd=3 version=1 // nla_reserve: msg 0x2b5110: attr <0x2b5164> 2: Reserved 12 (8) bytes at offset +4 nlmsg_len=32 // nla_put: msg 0x2b5110: attr <0x2b5164> 2: Wrote 8 bytes at offset +4 // 16 == msg.nm_protocol // 0 == msg.nm_flags // 0 == msg.nm_src.nl_family // 0 == msg.nm_src.nl_pid // 0 == msg.nm_src.nl_groups // 0 == msg.nm_dst.nl_family // 0 == msg.nm_dst.nl_pid // 0 == msg.nm_dst.nl_groups // 0 == msg.nm_creds.pid // 0 == msg.nm_creds.uid // 0 == msg.nm_creds.gid // 16 == msg.nm_nlh.nlmsg_type // 5 == msg.nm_nlh.nlmsg_flags // 14272 == msg.nm_nlh.nlmsg_pid // 4096 == msg.nm_size // 1 == msg.nm_refcnt // 20 00 00 00 10 00 05 00 af aa f6 54 c0 37 00 00 ..........T.7.. // 03 01 00 00 0c 00 02 00 6e 6c 38 30 32 31 31 00 ........nl80211. // nl_sendmsg: sent 32 bytes // 32 == nl_send_auto(sk, msg) // recvmsgs: Attempting to read from 0x2b5080 // 2c 07 00 00 10 00 00 00 af aa f6 54 c0 37 00 00 ,..........T.7.. // 01 02 00 00 0c 00 02 00 6e 6c 38 30 32 31 31 00 ........nl80211. // 06 00 01 00 16 00 00 00 08 00 03 00 01 00 00 00 ................ // 08 00 04 00 00 00 00 00 08 00 05 00 d5 00 00 00 ................ // 6c 06 06 00 14 00 01 00 08 00 01 00 01 00 00 00 l............... // 08 00 02 00 0e 00 00 00 14 00 02 00 08 00 01 00 ................ // <trimmed> // 63 6f 6e 66 69 67 00 00 18 00 02 00 08 00 02 00 config.......... // 04 00 00 00 09 00 01 00 73 63 61 6e 00 00 00 00 ........scan.... // 1c 00 03 00 08 00 02 00 05 00 00 00 0f 00 01 00 ................ // 72 65 67 75 6c 61 74 6f 72 79 00 00 18 00 04 00 regulatory...... // 08 00 02 00 06 00 00 00 09 00 01 00 6d 6c 6d 65 ............mlme // 00 00 00 00 18 00 05 00 08 00 02 00 07 00 00 00 ................ // 0b 00 01 00 76 65 6e 64 6f 72 00 00 ....vendor.. // recvmsgs: recvmsgs(0x2b5080): Read 1836 bytes // recvmsgs: recvmsgs(0x2b5080): Processing valid message... // __nlmsg_alloc: msg 0x2ba160: Allocated new message, maxlen=1836 // 16 == msg.nm_protocol // 0 == msg.nm_flags // 16 == msg.nm_src.nl_family // 0 == msg.nm_src.nl_pid // 0 == msg.nm_src.nl_groups // 0 == msg.nm_dst.nl_family // 0 == msg.nm_dst.nl_pid // 0 == msg.nm_dst.nl_groups // 0 == msg.nm_creds.pid // 0 == msg.nm_creds.uid // 0 == msg.nm_creds.gid // 16 == msg.nm_nlh.nlmsg_type // 0 == msg.nm_nlh.nlmsg_flags // 14272 == msg.nm_nlh.nlmsg_pid // 1836 == msg.nm_size // 1 == msg.nm_refcnt // 2c 07 00 00 10 00 00 00 af aa f6 54 c0 37 00 00 ,..........T.7.. // 01 02 00 00 0c 00 02 00 6e 6c 38 30 32 31 31 00 ........nl80211. // 06 00 01 00 16 00 00 00 08 00 03 00 01 00 00 00 ................ // 08 00 04 00 00 00 00 00 08 00 05 00 d5 00 00 00 ................ // 6c 06 06 00 14 00 01 00 08 00 01 00 01 00 00 00 l............... // 08 00 02 00 0e 00 00 00 14 00 02 00 08 00 01 00 ................ // <trimmed> // 63 6f 6e 66 69 67 00 00 18 00 02 00 08 00 02 00 config.......... // 04 00 00 00 09 00 01 00 73 63 61 6e 00 00 00 00 ........scan.... // 1c 00 03 00 08 00 02 00 05 00 00 00 0f 00 01 00 ................ // 72 65 67 75 6c 61 74 6f 72 79 00 00 18 00 04 00 regulatory...... // 08 00 02 00 06 00 00 00 09 00 01 00 6d 6c 6d 65 ............mlme // 00 00 00 00 18 00 05 00 08 00 02 00 ............ // nlmsg_free: Returned message reference 0x2ba160, 0 remaining // nlmsg_free: msg 0x2ba160: Freed // 0 == nl_recvmsgs_default(sk) // nl_cache_mngt_unregister: Unregistered cache operations genl/family """ def callback_send(sk, msg): assert 16 == msg.nm_protocol assert 0 == msg.nm_flags assert 0 == msg.nm_src.nl_family assert 0 == msg.nm_src.nl_pid assert 0 == msg.nm_src.nl_groups assert 0 == msg.nm_dst.nl_family assert 0 == msg.nm_dst.nl_pid assert 0 == msg.nm_dst.nl_groups assert msg.nm_creds is None assert 16 == msg.nm_nlh.nlmsg_type assert 5 == msg.nm_nlh.nlmsg_flags assert 100 < msg.nm_nlh.nlmsg_pid assert 1 == msg.nm_refcnt hdr = nlmsg_hdr(msg) iov = hdr.bytearray[:hdr.nlmsg_len] dump_hex(logging.getLogger().debug, iov, len(iov), 0) return nl_send_iovec(sk, msg, iov, 1) def callback_recv(sk, nla, buf, creds): n = nl_recv(sk, nla, buf, creds) dump_hex(logging.getLogger().debug, buf, len(buf), 0) return n def callback_recv_msg(msg, _): assert 16 == msg.nm_protocol assert 0 == msg.nm_flags assert 16 == msg.nm_src.nl_family assert 0 == msg.nm_src.nl_pid assert 0 == msg.nm_src.nl_groups assert 0 == msg.nm_dst.nl_family assert 0 == msg.nm_dst.nl_pid assert 0 == msg.nm_dst.nl_groups assert msg.nm_creds is None assert 16 == msg.nm_nlh.nlmsg_type assert 0 == msg.nm_nlh.nlmsg_flags assert 100 < msg.nm_nlh.nlmsg_pid assert 1000 < msg.nm_size assert 1 == msg.nm_refcnt dump_hex(logging.getLogger().debug, msg.nm_nlh.bytearray, nlmsg_datalen(msg.nm_nlh), 0) return NL_OK del log[:] sk_main = nl_socket_alloc() nl_cb_overwrite_send(sk_main.s_cb, callback_send) nl_cb_overwrite_recv(sk_main.s_cb, callback_recv) genl_connect(sk_main) ret = genl_family_alloc() genl_family_set_name(ret, b'nl80211') msg_main = nlmsg_alloc() genlmsg_put(msg_main, NL_AUTO_PORT, NL_AUTO_SEQ, GENL_ID_CTRL, 0, 0, CTRL_CMD_GETFAMILY, 1) nla_put_string(msg_main, CTRL_ATTR_FAMILY_NAME, b'nl80211') nl_socket_modify_cb(sk_main, NL_CB_VALID, NL_CB_CUSTOM, callback_recv_msg, None) assert 32 == nl_send_auto(sk_main, msg_main) assert 0 == nl_recvmsgs_default(sk_main) nl_socket_free(sk_main) assert match('nl_object_alloc: Allocated new object 0x[a-f0-9]+', log, True) assert match('nlmsg_alloc: msg 0x[a-f0-9]+: Allocated new message, maxlen=4096', log, True) assert match('nlmsg_put: msg 0x[a-f0-9]+: Added netlink header type=16, flags=0, pid=0, seq=0', log, True) assert match('nlmsg_reserve: msg 0x[a-f0-9]+: Reserved 4 \(4\) bytes, pad=4, nlmsg_len=20', log, True) assert match('genlmsg_put: msg 0x[a-f0-9]+: Added generic netlink header cmd=3 version=1', log, True) assert match( 'nla_reserve: msg 0x[a-f0-9]+: attr <0x[a-f0-9]+> 2: Reserved 12 \(8\) bytes at offset \+4 nlmsg_len=32', log, True) assert match('nla_put: msg 0x[a-f0-9]+: attr <0x[a-f0-9]+> 2: Wrote 8 bytes at offset \+4', log, True) assert match('dump_hex: 20 00 00 00 10 00 05 00 .. .. .. .. .. .. 00 00 ...............', log, True) assert match('dump_hex: 03 01 00 00 0c 00 02 00 6e 6c 38 30 32 31 31 00 ........nl80211.', log) assert match('nl_sendmsg: sent 32 bytes', log) assert match('recvmsgs: Attempting to read from 0x[a-f0-9]+', log, True) assert match('dump_hex: .. .. 00 00 10 00 00 00 .. .. .. .. .. .. 00 00 ................', log, True) assert match('dump_hex: 01 02 00 00 0c 00 02 00 6e 6c 38 30 32 31 31 00 ........nl80211.', log) assert match('dump_hex: 06 00 01 00 .. 00 00 00 08 00 03 00 01 00 00 00 ................', log, True) assert match('dump_hex: 08 00 04 00 00 00 00 00 08 00 05 00 .. 00 00 00 ................', log, True) for i in range(len(log)): if re.match(r'recvmsgs: recvmsgs\(0x[a-f0-9]+\): Read \d{4,} bytes', log[i]): log = log[i:] break assert match('recvmsgs: recvmsgs\(0x[a-f0-9]+\): Read \d{3,} bytes', log, True) assert match('recvmsgs: recvmsgs\(0x[a-f0-9]+\): Processing valid message...', log, True) assert match('nlmsg_alloc: msg 0x[a-f0-9]+: Allocated new message, maxlen=\d{3,}', log, True) assert match('dump_hex: .. .. 00 00 10 00 00 00 .. .. .. .. .. .. 00 00 ................', log, True) assert match('dump_hex: 01 02 00 00 0c 00 02 00 6e 6c 38 30 32 31 31 00 ........nl80211.', log) assert match('dump_hex: 06 00 01 00 .. 00 00 00 08 00 03 00 01 00 00 00 ................', log, True) assert match('dump_hex: 08 00 04 00 00 00 00 00 08 00 05 00 .. 00 00 00 ................', log, True) while log and log[0].startswith('dump_hex:'): log.pop(0) assert not log