From ec167d39b803df4ebdfba0741be8d620e51cd2a7 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Tue, 17 Jan 2023 11:44:26 +0100 Subject: nl80211: refactor command bitmask handling - add missing overflow check - make array size dynamic - set all bits if command id is not specified - add helper function for filling command bits Signed-off-by: Felix Fietkau --- lib/nl80211.c | 88 +++++++++++++++++++++++++++++++++-------------------------- 1 file changed, 50 insertions(+), 38 deletions(-) (limited to 'lib') diff --git a/lib/nl80211.c b/lib/nl80211.c index d182d7a..58e49bb 100644 --- a/lib/nl80211.c +++ b/lib/nl80211.c @@ -43,6 +43,8 @@ limitations under the License. #include "ucode/module.h" +#define DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d)) + #define err_return(code, ...) do { set_error(code, __VA_ARGS__); return NULL; } while(0) /* Modified downstream nl80211.h headers may disable certain unsupported @@ -51,6 +53,8 @@ limitations under the License. #define NL80211_ATTR_NOT_IMPLEMENTED 0x10000 +#define NL80211_CMDS_BITMAP_SIZE DIV_ROUND_UP(NL80211_CMD_MAX + 1, 32) + static struct { int code; char *msg; @@ -2149,7 +2153,7 @@ struct waitfor_ctx { uint8_t cmd; uc_vm_t *vm; uc_value_t *res; - uint32_t cmds[8]; + uint32_t cmds[NL80211_CMDS_BITMAP_SIZE]; }; static int @@ -2158,28 +2162,25 @@ cb_event(struct nl_msg *msg, void *arg) struct nlmsghdr *hdr = nlmsg_hdr(msg); struct genlmsghdr *gnlh = nlmsg_data(hdr); struct waitfor_ctx *s = arg; - bool rv, match = true; + bool rv; uc_value_t *o; - if (s->cmds[0] || s->cmds[1] || s->cmds[2] || s->cmds[3] || - s->cmds[4] || s->cmds[5] || s->cmds[6] || s->cmds[7]) { - match = (s->cmds[gnlh->cmd / 32] & (1 << (gnlh->cmd % 32))); - } + if (gnlh->cmd > NL80211_CMD_MAX || + !(s->cmds[gnlh->cmd / 32] & (1 << (gnlh->cmd % 32)))) + return NL_SKIP; - if (match) { - o = ucv_object_new(s->vm); + o = ucv_object_new(s->vm); - rv = uc_nl_convert_attrs(msg, - genlmsg_attrdata(gnlh, 0), genlmsg_attrlen(gnlh, 0), - 0, nl80211_msg.attrs, nl80211_msg.nattrs, s->vm, o); + rv = uc_nl_convert_attrs(msg, + genlmsg_attrdata(gnlh, 0), genlmsg_attrlen(gnlh, 0), + 0, nl80211_msg.attrs, nl80211_msg.nattrs, s->vm, o); - if (rv) - s->res = o; - else - ucv_put(o); + if (rv) + s->res = o; + else + ucv_put(o); - s->cmd = gnlh->cmd; - } + s->cmd = gnlh->cmd; return NL_SKIP; } @@ -2190,6 +2191,35 @@ cb_seq(struct nl_msg *msg, void *arg) return NL_OK; } +static bool +uc_nl_fill_cmds(uint32_t *cmd_bits, uc_value_t *cmds) +{ + if (ucv_type(cmds) == UC_ARRAY) { + for (size_t i = 0; i < ucv_array_length(cmds); i++) { + int64_t n = ucv_int64_get(ucv_array_get(cmds, i)); + + if (errno || n < 0 || n > NL80211_CMD_MAX) + return false; + + cmd_bits[n / 32] |= (1 << (n % 32)); + } + } + else if (ucv_type(cmds) == UC_INTEGER) { + int64_t n = ucv_int64_get(cmds); + + if (errno || n < 0 || n > 255) + return false; + + cmd_bits[n / 32] |= (1 << (n % 32)); + } + else if (!cmds) + memset(cmd_bits, 0xff, NL80211_CMDS_BITMAP_SIZE * sizeof(*cmd_bits)); + else + return false; + + return true; +} + static uc_value_t * uc_nl_waitfor(uc_vm_t *vm, size_t nargs) { @@ -2200,11 +2230,9 @@ uc_nl_waitfor(uc_vm_t *vm, size_t nargs) struct waitfor_ctx ctx = { .vm = vm }; struct nl_cb *cb; int ms = -1, err; - int64_t n; - size_t i; if (timeout) { - n = ucv_int64_get(timeout); + int64_t n = ucv_int64_get(timeout); if (ucv_type(timeout) != UC_INTEGER || n < INT32_MIN || n > INT32_MAX) err_return(NLE_INVAL, "Invalid timeout specified"); @@ -2212,24 +2240,8 @@ uc_nl_waitfor(uc_vm_t *vm, size_t nargs) ms = (int)n; } - if (ucv_type(cmds) == UC_ARRAY) { - for (i = 0; i < ucv_array_length(cmds); i++) { - n = ucv_int64_get(ucv_array_get(cmds, i)); - - if (n < 0 || n > 255) - err_return(NLE_INVAL, "Invalid command ID specified"); - - ctx.cmds[n / 32] |= (1 << (n % 32)); - } - } - else if (ucv_type(cmds) == UC_INTEGER) { - n = ucv_int64_get(cmds); - - if (n < 0 || n > 255) - err_return(NLE_INVAL, "Invalid command ID specified"); - - ctx.cmds[n / 32] |= (1 << (n % 32)); - } + if (!uc_nl_fill_cmds(ctx.cmds, cmds)) + err_return(NLE_INVAL, "Invalid command ID specified"); if (!nl80211_conn.evsock) { if (!uc_nl_connect_sock(&nl80211_conn.evsock, true) || -- cgit v1.2.3 From 6704ec0d5b2923100fda9e2cb7efead7b9836da2 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Thu, 19 Jan 2023 11:01:20 +0100 Subject: nl80211: add support for registering an uloop based listener Can be used to capture nl80211 messages in an event driven program Signed-off-by: Felix Fietkau --- CMakeLists.txt | 3 +- lib/nl80211.c | 246 ++++++++++++++++++++++++++++++++++++++++++++++++++++----- 2 files changed, 228 insertions(+), 21 deletions(-) (limited to 'lib') diff --git a/CMakeLists.txt b/CMakeLists.txt index 6506b1a..6d76f3a 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -154,13 +154,14 @@ ENDIF() IF(NL80211_SUPPORT) FIND_LIBRARY(nl NAMES nl-tiny) + FIND_LIBRARY(ubox NAMES ubox) FIND_PATH(nl_include_dir NAMES netlink/msg.h PATH_SUFFIXES libnl-tiny) INCLUDE_DIRECTORIES(${nl_include_dir}) SET(LIBRARIES ${LIBRARIES} nl80211_lib) ADD_LIBRARY(nl80211_lib MODULE lib/nl80211.c) SET_TARGET_PROPERTIES(nl80211_lib PROPERTIES OUTPUT_NAME nl80211 PREFIX "") TARGET_LINK_OPTIONS(nl80211_lib PRIVATE ${UCODE_MODULE_LINK_OPTIONS}) - TARGET_LINK_LIBRARIES(nl80211_lib ${nl}) + TARGET_LINK_LIBRARIES(nl80211_lib ${nl} ${ubox}) ENDIF() IF(RESOLV_SUPPORT) diff --git a/lib/nl80211.c b/lib/nl80211.c index 58e49bb..f3e63bb 100644 --- a/lib/nl80211.c +++ b/lib/nl80211.c @@ -40,6 +40,7 @@ limitations under the License. #include #include +#include #include "ucode/module.h" @@ -76,6 +77,15 @@ set_error(int errcode, const char *fmt, ...) { } } +static uc_resource_type_t *listener_type; +static uc_value_t *listener_registry; +static uc_vm_t *listener_vm; + +typedef struct { + uint32_t cmds[NL80211_CMDS_BITMAP_SIZE]; + size_t index; +} uc_nl_listener_t; + static bool uc_nl_parse_u32(uc_value_t *val, uint32_t *n) { @@ -1817,6 +1827,8 @@ static struct { struct nl_cache *cache; struct genl_family *nl80211; struct genl_family *nlctrl; + struct uloop_fd evsock_fd; + struct nl_cb *evsock_cb; } nl80211_conn; typedef enum { @@ -2156,29 +2168,90 @@ struct waitfor_ctx { uint32_t cmds[NL80211_CMDS_BITMAP_SIZE]; }; +static uc_value_t * +uc_nl_prepare_event(uc_vm_t *vm, struct nl_msg *msg) +{ + struct nlmsghdr *hdr = nlmsg_hdr(msg); + struct genlmsghdr *gnlh = nlmsg_data(hdr); + uc_value_t *o = ucv_object_new(vm); + + if (!uc_nl_convert_attrs(msg, genlmsg_attrdata(gnlh, 0), + genlmsg_attrlen(gnlh, 0), 0, + nl80211_msg.attrs, nl80211_msg.nattrs, vm, o)) { + ucv_put(o); + return NULL; + } + + return o; +} + +static int +cb_listener_event(struct nl_msg *msg, void *arg) +{ + struct nlmsghdr *hdr = nlmsg_hdr(msg); + struct genlmsghdr *gnlh = nlmsg_data(hdr); + uc_vm_t *vm = listener_vm; + + if (!nl80211_conn.evsock_fd.registered || !vm) + return NL_SKIP; + + for (size_t i = 0; i < ucv_array_length(listener_registry); i += 2) { + uc_value_t *this = ucv_array_get(listener_registry, i); + uc_value_t *func = ucv_array_get(listener_registry, i + 1); + uc_nl_listener_t *l; + uc_value_t *o, *data; + + l = ucv_resource_data(this, "nl80211.listener"); + if (!l) + continue; + + if (gnlh->cmd > NL80211_CMD_MAX || + !(l->cmds[gnlh->cmd / 32] & (1 << (gnlh->cmd % 32)))) + continue; + + if (!ucv_is_callable(func)) + continue; + + data = uc_nl_prepare_event(vm, msg); + if (!data) + return NL_SKIP; + + o = ucv_object_new(vm); + ucv_object_add(o, "cmd", ucv_int64_new(gnlh->cmd)); + ucv_object_add(o, "msg", data); + + uc_vm_stack_push(vm, ucv_get(this)); + uc_vm_stack_push(vm, ucv_get(func)); + uc_vm_stack_push(vm, o); + + if (uc_vm_call(vm, true, 1) != EXCEPTION_NONE) { + uloop_end(); + return NL_STOP; + } + + ucv_put(uc_vm_stack_pop(vm)); + } + + return NL_SKIP; +} + static int cb_event(struct nl_msg *msg, void *arg) { struct nlmsghdr *hdr = nlmsg_hdr(msg); struct genlmsghdr *gnlh = nlmsg_data(hdr); struct waitfor_ctx *s = arg; - bool rv; uc_value_t *o; + cb_listener_event(msg, arg); + if (gnlh->cmd > NL80211_CMD_MAX || !(s->cmds[gnlh->cmd / 32] & (1 << (gnlh->cmd % 32)))) return NL_SKIP; - o = ucv_object_new(s->vm); - - rv = uc_nl_convert_attrs(msg, - genlmsg_attrdata(gnlh, 0), genlmsg_attrlen(gnlh, 0), - 0, nl80211_msg.attrs, nl80211_msg.nattrs, s->vm, o); - - if (rv) + o = uc_nl_prepare_event(s->vm, msg); + if (o) s->res = o; - else - ucv_put(o); s->cmd = gnlh->cmd; @@ -2220,6 +2293,29 @@ uc_nl_fill_cmds(uint32_t *cmd_bits, uc_value_t *cmds) return true; } +static bool +uc_nl_evsock_init(void) +{ + if (nl80211_conn.evsock) + return true; + + if (!uc_nl_connect_sock(&nl80211_conn.evsock, true)) + return false; + + if (!uc_nl_subscribe(nl80211_conn.evsock, "nl80211", "config") || + !uc_nl_subscribe(nl80211_conn.evsock, "nl80211", "scan") || + !uc_nl_subscribe(nl80211_conn.evsock, "nl80211", "regulatory") || + !uc_nl_subscribe(nl80211_conn.evsock, "nl80211", "mlme") || + !uc_nl_subscribe(nl80211_conn.evsock, "nl80211", "vendor") || + !uc_nl_subscribe(nl80211_conn.evsock, "nl80211", "nan")) { + nl_socket_free(nl80211_conn.evsock); + nl80211_conn.evsock = NULL; + return false; + } + + return true; +} + static uc_value_t * uc_nl_waitfor(uc_vm_t *vm, size_t nargs) { @@ -2243,16 +2339,8 @@ uc_nl_waitfor(uc_vm_t *vm, size_t nargs) if (!uc_nl_fill_cmds(ctx.cmds, cmds)) err_return(NLE_INVAL, "Invalid command ID specified"); - if (!nl80211_conn.evsock) { - if (!uc_nl_connect_sock(&nl80211_conn.evsock, true) || - !uc_nl_subscribe(nl80211_conn.evsock, "nl80211", "config") || - !uc_nl_subscribe(nl80211_conn.evsock, "nl80211", "scan") || - !uc_nl_subscribe(nl80211_conn.evsock, "nl80211", "regulatory") || - !uc_nl_subscribe(nl80211_conn.evsock, "nl80211", "mlme") || - !uc_nl_subscribe(nl80211_conn.evsock, "nl80211", "vendor") || - !uc_nl_subscribe(nl80211_conn.evsock, "nl80211", "nan")) - return NULL; - } + if (!uc_nl_evsock_init()) + return NULL; cb = nl_cb_alloc(NL_CB_DEFAULT); @@ -2380,6 +2468,113 @@ uc_nl_request(uc_vm_t *vm, size_t nargs) } } +static void +uc_nl_listener_cb(struct uloop_fd *fd, unsigned int events) +{ + nl_recvmsgs(nl80211_conn.evsock, nl80211_conn.evsock_cb); +} + +static uc_value_t * +uc_nl_listener(uc_vm_t *vm, size_t nargs) +{ + struct uloop_fd *fd = &nl80211_conn.evsock_fd; + uc_nl_listener_t *l; + uc_value_t *cb_func = uc_fn_arg(0); + uc_value_t *cmds = uc_fn_arg(1); + uc_value_t *rv; + size_t i; + + if (!ucv_is_callable(cb_func)) { + uc_vm_raise_exception(vm, EXCEPTION_TYPE, "Invalid callback"); + return NULL; + } + + if (!uc_nl_evsock_init()) + return NULL; + + if (!fd->registered) { + fd->fd = nl_socket_get_fd(nl80211_conn.evsock); + fd->cb = uc_nl_listener_cb; + uloop_fd_add(fd, ULOOP_READ); + } + + if (!nl80211_conn.evsock_cb) { + struct nl_cb *cb = nl_cb_alloc(NL_CB_DEFAULT); + + if (!cb) + err_return(NLE_NOMEM, NULL); + + nl_cb_set(cb, NL_CB_SEQ_CHECK, NL_CB_CUSTOM, cb_seq, NULL); + nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, cb_listener_event, NULL); + nl80211_conn.evsock_cb = cb; + } + + for (i = 0; i < ucv_array_length(listener_registry); i += 2) { + if (!ucv_array_get(listener_registry, i)) + break; + } + + ucv_array_set(listener_registry, i + 1, cb_func); + l = xalloc(sizeof(*l)); + l->index = i; + if (!uc_nl_fill_cmds(l->cmds, cmds)) { + uc_vm_raise_exception(vm, EXCEPTION_TYPE, "Invalid command ID"); + free(l); + return NULL; + } + + rv = uc_resource_new(listener_type, l); + ucv_array_set(listener_registry, i, rv); + listener_vm = vm; + + return rv; +} + +static void +uc_nl_listener_free(void *arg) +{ + uc_nl_listener_t *l = arg; + + ucv_array_set(listener_registry, l->index, NULL); + ucv_array_set(listener_registry, l->index + 1, NULL); + free(l); +} + +static uc_value_t * +uc_nl_listener_set_commands(uc_vm_t *vm, size_t nargs) +{ + uc_nl_listener_t *l = uc_fn_thisval("nl80211.listener"); + uc_value_t *cmds = uc_fn_arg(0); + + if (!l) + return NULL; + + memset(l->cmds, 0, sizeof(l->cmds)); + if (!uc_nl_fill_cmds(l->cmds, cmds)) + uc_vm_raise_exception(vm, EXCEPTION_TYPE, "Invalid command ID"); + + return NULL; +} + +static uc_value_t * +uc_nl_listener_close(uc_vm_t *vm, size_t nargs) +{ + uc_nl_listener_t **lptr = uc_fn_this("nl80211.listener"); + uc_nl_listener_t *l; + + if (!lptr) + return NULL; + + l = *lptr; + if (!l) + return NULL; + + *lptr = NULL; + uc_nl_listener_free(l); + + return NULL; +} + static void register_constants(uc_vm_t *vm, uc_value_t *scope) @@ -2530,12 +2725,23 @@ static const uc_function_list_t global_fns[] = { { "error", uc_nl_error }, { "request", uc_nl_request }, { "waitfor", uc_nl_waitfor }, + { "listener", uc_nl_listener }, }; +static const uc_function_list_t listener_fns[] = { + { "set_commands", uc_nl_listener_set_commands }, + { "close", uc_nl_listener_close }, +}; + void uc_module_init(uc_vm_t *vm, uc_value_t *scope) { uc_function_list_register(scope, global_fns); + listener_type = uc_type_declare(vm, "nl80211.listener", listener_fns, uc_nl_listener_free); + listener_registry = ucv_array_new(vm); + + uc_vm_registry_set(vm, "nl80211.registry", listener_registry); + register_constants(vm, scope); } -- cgit v1.2.3