From 7084566a236fbc98beb11430d8d67dd08b2ac151 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Tue, 18 Aug 2020 18:36:05 -0700 Subject: [PATCH] tools/bpftool: Remove libbpf_internal.h usage in bpftool Most netlink-related functions were unique to bpftool usage, so I moved them into net.c. Few functions are still used by both bpftool and libbpf itself internally, so I've copy-pasted them (libbpf_nl_get_link, libbpf_netlink_open). It's a bit of duplication of code, but better separation of libbpf as a library with public API and bpftool, relying on unexposed functions in libbpf. Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200819013607.3607269-3-andriin@fb.com --- tools/bpf/bpftool/gen.c | 2 - tools/bpf/bpftool/net.c | 299 ++++++++++++++++++++++++++++++-- tools/lib/bpf/libbpf_internal.h | 12 -- tools/lib/bpf/netlink.c | 125 +------------ 4 files changed, 288 insertions(+), 150 deletions(-) diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index f61184653633..4033c46d83e7 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -19,11 +19,9 @@ #include #include -#include "bpf/libbpf_internal.h" #include "json_writer.h" #include "main.h" - #define MAX_OBJ_NAME_LEN 64 static void sanitize_identifier(char *name) diff --git a/tools/bpf/bpftool/net.c b/tools/bpf/bpftool/net.c index 56c3a2bae3ef..910e7bac6e9e 100644 --- a/tools/bpf/bpftool/net.c +++ b/tools/bpf/bpftool/net.c @@ -6,22 +6,27 @@ #include #include #include +#include #include #include #include #include #include #include +#include #include #include #include #include #include "bpf/nlattr.h" -#include "bpf/libbpf_internal.h" #include "main.h" #include "netlink_dumper.h" +#ifndef SOL_NETLINK +#define SOL_NETLINK 270 +#endif + struct ip_devname_ifindex { char devname[64]; int ifindex; @@ -85,6 +90,266 @@ static enum net_attach_type parse_attach_type(const char *str) return net_attach_type_size; } +typedef int (*dump_nlmsg_t)(void *cookie, void *msg, struct nlattr **tb); + +typedef int (*__dump_nlmsg_t)(struct nlmsghdr *nlmsg, dump_nlmsg_t, void *cookie); + +static int netlink_open(__u32 *nl_pid) +{ + struct sockaddr_nl sa; + socklen_t addrlen; + int one = 1, ret; + int sock; + + memset(&sa, 0, sizeof(sa)); + sa.nl_family = AF_NETLINK; + + sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); + if (sock < 0) + return -errno; + + if (setsockopt(sock, SOL_NETLINK, NETLINK_EXT_ACK, + &one, sizeof(one)) < 0) { + p_err("Netlink error reporting not supported"); + } + + if (bind(sock, (struct sockaddr *)&sa, sizeof(sa)) < 0) { + ret = -errno; + goto cleanup; + } + + addrlen = sizeof(sa); + if (getsockname(sock, (struct sockaddr *)&sa, &addrlen) < 0) { + ret = -errno; + goto cleanup; + } + + if (addrlen != sizeof(sa)) { + ret = -LIBBPF_ERRNO__INTERNAL; + goto cleanup; + } + + *nl_pid = sa.nl_pid; + return sock; + +cleanup: + close(sock); + return ret; +} + +static int netlink_recv(int sock, __u32 nl_pid, __u32 seq, + __dump_nlmsg_t _fn, dump_nlmsg_t fn, + void *cookie) +{ + bool multipart = true; + struct nlmsgerr *err; + struct nlmsghdr *nh; + char buf[4096]; + int len, ret; + + while (multipart) { + multipart = false; + len = recv(sock, buf, sizeof(buf), 0); + if (len < 0) { + ret = -errno; + goto done; + } + + if (len == 0) + break; + + for (nh = (struct nlmsghdr *)buf; NLMSG_OK(nh, len); + nh = NLMSG_NEXT(nh, len)) { + if (nh->nlmsg_pid != nl_pid) { + ret = -LIBBPF_ERRNO__WRNGPID; + goto done; + } + if (nh->nlmsg_seq != seq) { + ret = -LIBBPF_ERRNO__INVSEQ; + goto done; + } + if (nh->nlmsg_flags & NLM_F_MULTI) + multipart = true; + switch (nh->nlmsg_type) { + case NLMSG_ERROR: + err = (struct nlmsgerr *)NLMSG_DATA(nh); + if (!err->error) + continue; + ret = err->error; + libbpf_nla_dump_errormsg(nh); + goto done; + case NLMSG_DONE: + return 0; + default: + break; + } + if (_fn) { + ret = _fn(nh, fn, cookie); + if (ret) + return ret; + } + } + } + ret = 0; +done: + return ret; +} + +static int __dump_class_nlmsg(struct nlmsghdr *nlh, + dump_nlmsg_t dump_class_nlmsg, + void *cookie) +{ + struct nlattr *tb[TCA_MAX + 1], *attr; + struct tcmsg *t = NLMSG_DATA(nlh); + int len; + + len = nlh->nlmsg_len - NLMSG_LENGTH(sizeof(*t)); + attr = (struct nlattr *) ((void *) t + NLMSG_ALIGN(sizeof(*t))); + if (libbpf_nla_parse(tb, TCA_MAX, attr, len, NULL) != 0) + return -LIBBPF_ERRNO__NLPARSE; + + return dump_class_nlmsg(cookie, t, tb); +} + +static int netlink_get_class(int sock, unsigned int nl_pid, int ifindex, + dump_nlmsg_t dump_class_nlmsg, void *cookie) +{ + struct { + struct nlmsghdr nlh; + struct tcmsg t; + } req = { + .nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg)), + .nlh.nlmsg_type = RTM_GETTCLASS, + .nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST, + .t.tcm_family = AF_UNSPEC, + .t.tcm_ifindex = ifindex, + }; + int seq = time(NULL); + + req.nlh.nlmsg_seq = seq; + if (send(sock, &req, req.nlh.nlmsg_len, 0) < 0) + return -errno; + + return netlink_recv(sock, nl_pid, seq, __dump_class_nlmsg, + dump_class_nlmsg, cookie); +} + +static int __dump_qdisc_nlmsg(struct nlmsghdr *nlh, + dump_nlmsg_t dump_qdisc_nlmsg, + void *cookie) +{ + struct nlattr *tb[TCA_MAX + 1], *attr; + struct tcmsg *t = NLMSG_DATA(nlh); + int len; + + len = nlh->nlmsg_len - NLMSG_LENGTH(sizeof(*t)); + attr = (struct nlattr *) ((void *) t + NLMSG_ALIGN(sizeof(*t))); + if (libbpf_nla_parse(tb, TCA_MAX, attr, len, NULL) != 0) + return -LIBBPF_ERRNO__NLPARSE; + + return dump_qdisc_nlmsg(cookie, t, tb); +} + +static int netlink_get_qdisc(int sock, unsigned int nl_pid, int ifindex, + dump_nlmsg_t dump_qdisc_nlmsg, void *cookie) +{ + struct { + struct nlmsghdr nlh; + struct tcmsg t; + } req = { + .nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg)), + .nlh.nlmsg_type = RTM_GETQDISC, + .nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST, + .t.tcm_family = AF_UNSPEC, + .t.tcm_ifindex = ifindex, + }; + int seq = time(NULL); + + req.nlh.nlmsg_seq = seq; + if (send(sock, &req, req.nlh.nlmsg_len, 0) < 0) + return -errno; + + return netlink_recv(sock, nl_pid, seq, __dump_qdisc_nlmsg, + dump_qdisc_nlmsg, cookie); +} + +static int __dump_filter_nlmsg(struct nlmsghdr *nlh, + dump_nlmsg_t dump_filter_nlmsg, + void *cookie) +{ + struct nlattr *tb[TCA_MAX + 1], *attr; + struct tcmsg *t = NLMSG_DATA(nlh); + int len; + + len = nlh->nlmsg_len - NLMSG_LENGTH(sizeof(*t)); + attr = (struct nlattr *) ((void *) t + NLMSG_ALIGN(sizeof(*t))); + if (libbpf_nla_parse(tb, TCA_MAX, attr, len, NULL) != 0) + return -LIBBPF_ERRNO__NLPARSE; + + return dump_filter_nlmsg(cookie, t, tb); +} + +static int netlink_get_filter(int sock, unsigned int nl_pid, int ifindex, int handle, + dump_nlmsg_t dump_filter_nlmsg, void *cookie) +{ + struct { + struct nlmsghdr nlh; + struct tcmsg t; + } req = { + .nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg)), + .nlh.nlmsg_type = RTM_GETTFILTER, + .nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST, + .t.tcm_family = AF_UNSPEC, + .t.tcm_ifindex = ifindex, + .t.tcm_parent = handle, + }; + int seq = time(NULL); + + req.nlh.nlmsg_seq = seq; + if (send(sock, &req, req.nlh.nlmsg_len, 0) < 0) + return -errno; + + return netlink_recv(sock, nl_pid, seq, __dump_filter_nlmsg, + dump_filter_nlmsg, cookie); +} + +static int __dump_link_nlmsg(struct nlmsghdr *nlh, + dump_nlmsg_t dump_link_nlmsg, void *cookie) +{ + struct nlattr *tb[IFLA_MAX + 1], *attr; + struct ifinfomsg *ifi = NLMSG_DATA(nlh); + int len; + + len = nlh->nlmsg_len - NLMSG_LENGTH(sizeof(*ifi)); + attr = (struct nlattr *) ((void *) ifi + NLMSG_ALIGN(sizeof(*ifi))); + if (libbpf_nla_parse(tb, IFLA_MAX, attr, len, NULL) != 0) + return -LIBBPF_ERRNO__NLPARSE; + + return dump_link_nlmsg(cookie, ifi, tb); +} + +static int netlink_get_link(int sock, unsigned int nl_pid, + dump_nlmsg_t dump_link_nlmsg, void *cookie) +{ + struct { + struct nlmsghdr nlh; + struct ifinfomsg ifm; + } req = { + .nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)), + .nlh.nlmsg_type = RTM_GETLINK, + .nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST, + .ifm.ifi_family = AF_PACKET, + }; + int seq = time(NULL); + + req.nlh.nlmsg_seq = seq; + if (send(sock, &req, req.nlh.nlmsg_len, 0) < 0) + return -errno; + + return netlink_recv(sock, nl_pid, seq, __dump_link_nlmsg, + dump_link_nlmsg, cookie); +} + static int dump_link_nlmsg(void *cookie, void *msg, struct nlattr **tb) { struct bpf_netdev_t *netinfo = cookie; @@ -168,14 +433,14 @@ static int show_dev_tc_bpf(int sock, unsigned int nl_pid, tcinfo.array_len = 0; tcinfo.is_qdisc = false; - ret = libbpf_nl_get_class(sock, nl_pid, dev->ifindex, - dump_class_qdisc_nlmsg, &tcinfo); + ret = netlink_get_class(sock, nl_pid, dev->ifindex, + dump_class_qdisc_nlmsg, &tcinfo); if (ret) goto out; tcinfo.is_qdisc = true; - ret = libbpf_nl_get_qdisc(sock, nl_pid, dev->ifindex, - dump_class_qdisc_nlmsg, &tcinfo); + ret = netlink_get_qdisc(sock, nl_pid, dev->ifindex, + dump_class_qdisc_nlmsg, &tcinfo); if (ret) goto out; @@ -183,9 +448,9 @@ static int show_dev_tc_bpf(int sock, unsigned int nl_pid, filter_info.ifindex = dev->ifindex; for (i = 0; i < tcinfo.used_len; i++) { filter_info.kind = tcinfo.handle_array[i].kind; - ret = libbpf_nl_get_filter(sock, nl_pid, dev->ifindex, - tcinfo.handle_array[i].handle, - dump_filter_nlmsg, &filter_info); + ret = netlink_get_filter(sock, nl_pid, dev->ifindex, + tcinfo.handle_array[i].handle, + dump_filter_nlmsg, &filter_info); if (ret) goto out; } @@ -193,22 +458,22 @@ static int show_dev_tc_bpf(int sock, unsigned int nl_pid, /* root, ingress and egress handle */ handle = TC_H_ROOT; filter_info.kind = "root"; - ret = libbpf_nl_get_filter(sock, nl_pid, dev->ifindex, handle, - dump_filter_nlmsg, &filter_info); + ret = netlink_get_filter(sock, nl_pid, dev->ifindex, handle, + dump_filter_nlmsg, &filter_info); if (ret) goto out; handle = TC_H_MAKE(TC_H_CLSACT, TC_H_MIN_INGRESS); filter_info.kind = "clsact/ingress"; - ret = libbpf_nl_get_filter(sock, nl_pid, dev->ifindex, handle, - dump_filter_nlmsg, &filter_info); + ret = netlink_get_filter(sock, nl_pid, dev->ifindex, handle, + dump_filter_nlmsg, &filter_info); if (ret) goto out; handle = TC_H_MAKE(TC_H_CLSACT, TC_H_MIN_EGRESS); filter_info.kind = "clsact/egress"; - ret = libbpf_nl_get_filter(sock, nl_pid, dev->ifindex, handle, - dump_filter_nlmsg, &filter_info); + ret = netlink_get_filter(sock, nl_pid, dev->ifindex, handle, + dump_filter_nlmsg, &filter_info); if (ret) goto out; @@ -386,7 +651,7 @@ static int do_show(int argc, char **argv) struct bpf_attach_info attach_info = {}; int i, sock, ret, filter_idx = -1; struct bpf_netdev_t dev_array; - unsigned int nl_pid; + unsigned int nl_pid = 0; char err_buf[256]; if (argc == 2) { @@ -401,7 +666,7 @@ static int do_show(int argc, char **argv) if (ret) return -1; - sock = libbpf_netlink_open(&nl_pid); + sock = netlink_open(&nl_pid); if (sock < 0) { fprintf(stderr, "failed to open netlink sock\n"); return -1; @@ -416,7 +681,7 @@ static int do_show(int argc, char **argv) jsonw_start_array(json_wtr); NET_START_OBJECT; NET_START_ARRAY("xdp", "%s:\n"); - ret = libbpf_nl_get_link(sock, nl_pid, dump_link_nlmsg, &dev_array); + ret = netlink_get_link(sock, nl_pid, dump_link_nlmsg, &dev_array); NET_END_ARRAY("\n"); if (!ret) { diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h index 954bc2bd040c..65931e989eea 100644 --- a/tools/lib/bpf/libbpf_internal.h +++ b/tools/lib/bpf/libbpf_internal.h @@ -130,18 +130,6 @@ int bpf_object__section_size(const struct bpf_object *obj, const char *name, int bpf_object__variable_offset(const struct bpf_object *obj, const char *name, __u32 *off); -struct nlattr; -typedef int (*libbpf_dump_nlmsg_t)(void *cookie, void *msg, struct nlattr **tb); -int libbpf_netlink_open(unsigned int *nl_pid); -int libbpf_nl_get_link(int sock, unsigned int nl_pid, - libbpf_dump_nlmsg_t dump_link_nlmsg, void *cookie); -int libbpf_nl_get_class(int sock, unsigned int nl_pid, int ifindex, - libbpf_dump_nlmsg_t dump_class_nlmsg, void *cookie); -int libbpf_nl_get_qdisc(int sock, unsigned int nl_pid, int ifindex, - libbpf_dump_nlmsg_t dump_qdisc_nlmsg, void *cookie); -int libbpf_nl_get_filter(int sock, unsigned int nl_pid, int ifindex, int handle, - libbpf_dump_nlmsg_t dump_filter_nlmsg, void *cookie); - struct btf_ext_info { /* * info points to the individual info section (e.g. func_info and diff --git a/tools/lib/bpf/netlink.c b/tools/lib/bpf/netlink.c index 312f887570b2..2465538a5ba9 100644 --- a/tools/lib/bpf/netlink.c +++ b/tools/lib/bpf/netlink.c @@ -22,6 +22,8 @@ #define SOL_NETLINK 270 #endif +typedef int (*libbpf_dump_nlmsg_t)(void *cookie, void *msg, struct nlattr **tb); + typedef int (*__dump_nlmsg_t)(struct nlmsghdr *nlmsg, libbpf_dump_nlmsg_t, void *cookie); @@ -31,7 +33,7 @@ struct xdp_id_md { struct xdp_link_info info; }; -int libbpf_netlink_open(__u32 *nl_pid) +static int libbpf_netlink_open(__u32 *nl_pid) { struct sockaddr_nl sa; socklen_t addrlen; @@ -283,6 +285,9 @@ static int get_xdp_info(void *cookie, void *msg, struct nlattr **tb) return 0; } +static int libbpf_nl_get_link(int sock, unsigned int nl_pid, + libbpf_dump_nlmsg_t dump_link_nlmsg, void *cookie); + int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info, size_t info_size, __u32 flags) { @@ -368,121 +373,3 @@ int libbpf_nl_get_link(int sock, unsigned int nl_pid, return bpf_netlink_recv(sock, nl_pid, seq, __dump_link_nlmsg, dump_link_nlmsg, cookie); } - -static int __dump_class_nlmsg(struct nlmsghdr *nlh, - libbpf_dump_nlmsg_t dump_class_nlmsg, - void *cookie) -{ - struct nlattr *tb[TCA_MAX + 1], *attr; - struct tcmsg *t = NLMSG_DATA(nlh); - int len; - - len = nlh->nlmsg_len - NLMSG_LENGTH(sizeof(*t)); - attr = (struct nlattr *) ((void *) t + NLMSG_ALIGN(sizeof(*t))); - if (libbpf_nla_parse(tb, TCA_MAX, attr, len, NULL) != 0) - return -LIBBPF_ERRNO__NLPARSE; - - return dump_class_nlmsg(cookie, t, tb); -} - -int libbpf_nl_get_class(int sock, unsigned int nl_pid, int ifindex, - libbpf_dump_nlmsg_t dump_class_nlmsg, void *cookie) -{ - struct { - struct nlmsghdr nlh; - struct tcmsg t; - } req = { - .nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg)), - .nlh.nlmsg_type = RTM_GETTCLASS, - .nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST, - .t.tcm_family = AF_UNSPEC, - .t.tcm_ifindex = ifindex, - }; - int seq = time(NULL); - - req.nlh.nlmsg_seq = seq; - if (send(sock, &req, req.nlh.nlmsg_len, 0) < 0) - return -errno; - - return bpf_netlink_recv(sock, nl_pid, seq, __dump_class_nlmsg, - dump_class_nlmsg, cookie); -} - -static int __dump_qdisc_nlmsg(struct nlmsghdr *nlh, - libbpf_dump_nlmsg_t dump_qdisc_nlmsg, - void *cookie) -{ - struct nlattr *tb[TCA_MAX + 1], *attr; - struct tcmsg *t = NLMSG_DATA(nlh); - int len; - - len = nlh->nlmsg_len - NLMSG_LENGTH(sizeof(*t)); - attr = (struct nlattr *) ((void *) t + NLMSG_ALIGN(sizeof(*t))); - if (libbpf_nla_parse(tb, TCA_MAX, attr, len, NULL) != 0) - return -LIBBPF_ERRNO__NLPARSE; - - return dump_qdisc_nlmsg(cookie, t, tb); -} - -int libbpf_nl_get_qdisc(int sock, unsigned int nl_pid, int ifindex, - libbpf_dump_nlmsg_t dump_qdisc_nlmsg, void *cookie) -{ - struct { - struct nlmsghdr nlh; - struct tcmsg t; - } req = { - .nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg)), - .nlh.nlmsg_type = RTM_GETQDISC, - .nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST, - .t.tcm_family = AF_UNSPEC, - .t.tcm_ifindex = ifindex, - }; - int seq = time(NULL); - - req.nlh.nlmsg_seq = seq; - if (send(sock, &req, req.nlh.nlmsg_len, 0) < 0) - return -errno; - - return bpf_netlink_recv(sock, nl_pid, seq, __dump_qdisc_nlmsg, - dump_qdisc_nlmsg, cookie); -} - -static int __dump_filter_nlmsg(struct nlmsghdr *nlh, - libbpf_dump_nlmsg_t dump_filter_nlmsg, - void *cookie) -{ - struct nlattr *tb[TCA_MAX + 1], *attr; - struct tcmsg *t = NLMSG_DATA(nlh); - int len; - - len = nlh->nlmsg_len - NLMSG_LENGTH(sizeof(*t)); - attr = (struct nlattr *) ((void *) t + NLMSG_ALIGN(sizeof(*t))); - if (libbpf_nla_parse(tb, TCA_MAX, attr, len, NULL) != 0) - return -LIBBPF_ERRNO__NLPARSE; - - return dump_filter_nlmsg(cookie, t, tb); -} - -int libbpf_nl_get_filter(int sock, unsigned int nl_pid, int ifindex, int handle, - libbpf_dump_nlmsg_t dump_filter_nlmsg, void *cookie) -{ - struct { - struct nlmsghdr nlh; - struct tcmsg t; - } req = { - .nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg)), - .nlh.nlmsg_type = RTM_GETTFILTER, - .nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST, - .t.tcm_family = AF_UNSPEC, - .t.tcm_ifindex = ifindex, - .t.tcm_parent = handle, - }; - int seq = time(NULL); - - req.nlh.nlmsg_seq = seq; - if (send(sock, &req, req.nlh.nlmsg_len, 0) < 0) - return -errno; - - return bpf_netlink_recv(sock, nl_pid, seq, __dump_filter_nlmsg, - dump_filter_nlmsg, cookie); -}