bpf: sockmap sample test for bpf_msg_pull_data

This adds an option to test the msg_pull_data helper. This
uses two options txmsg_start and txmsg_end to let the user
specify start and end bytes to pull.

The options can be used with txmsg_apply, txmsg_cork options
as well as with any of the basic tests, txmsg, txmsg_redir and
txmsg_drop (plus noisy variants) to run pull_data inline with
those tests. By giving user direct control over the variables
we can easily do negative testing as well as positive tests.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

diff --git a/samples/sockmap/sockmap_kern.c b/samples/sockmap/sockmap_kern.c
index 8b6c34cd5f465635b78d04e991b0bd1e6f2794e6..9ad5ba79c85ae1a16710a337e32d4aaf08bfe776 100644 (file)
--- a/samples/sockmap/sockmap_kern.c
+++ b/samples/sockmap/sockmap_kern.c
@@ -71,6 +71,14 @@ struct bpf_map_def SEC("maps") sock_cork_bytes = {
        .max_entries = 1
 };
 
+struct bpf_map_def SEC("maps") sock_pull_bytes = {
+       .type = BPF_MAP_TYPE_ARRAY,
+       .key_size = sizeof(int),
+       .value_size = sizeof(int),
+       .max_entries = 2
+};
+
+
 SEC("sk_skb1")
 int bpf_prog1(struct __sk_buff *skb)
 {
@@ -137,7 +145,8 @@ int bpf_sockmap(struct bpf_sock_ops *skops)
 SEC("sk_msg1")
 int bpf_prog4(struct sk_msg_md *msg)
 {
-       int *bytes, zero = 0;
+       int *bytes, zero = 0, one = 1;
+       int *start, *end;
 
        bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
        if (bytes)
@@ -145,15 +154,18 @@ int bpf_prog4(struct sk_msg_md *msg)
        bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
        if (bytes)
                bpf_msg_cork_bytes(msg, *bytes);
+       start = bpf_map_lookup_elem(&sock_pull_bytes, &zero);
+       end = bpf_map_lookup_elem(&sock_pull_bytes, &one);
+       if (start && end)
+               bpf_msg_pull_data(msg, *start, *end, 0);
        return SK_PASS;
 }
 
 SEC("sk_msg2")
 int bpf_prog5(struct sk_msg_md *msg)
 {
-       void *data_end = (void *)(long) msg->data_end;
-       void *data = (void *)(long) msg->data;
-       int *bytes, err1 = -1, err2 = -1, zero = 0;
+       int err1 = -1, err2 = -1, zero = 0, one = 1;
+       int *bytes, *start, *end, len1, len2;
 
        bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
        if (bytes)
@@ -161,17 +173,32 @@ int bpf_prog5(struct sk_msg_md *msg)
        bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
        if (bytes)
                err2 = bpf_msg_cork_bytes(msg, *bytes);
+       len1 = (__u64)msg->data_end - (__u64)msg->data;
+       start = bpf_map_lookup_elem(&sock_pull_bytes, &zero);
+       end = bpf_map_lookup_elem(&sock_pull_bytes, &one);
+       if (start && end) {
+               int err;
+
+               bpf_printk("sk_msg2: pull(%i:%i)\n",
+                          start ? *start : 0, end ? *end : 0);
+               err = bpf_msg_pull_data(msg, *start, *end, 0);
+               if (err)
+                       bpf_printk("sk_msg2: pull_data err %i\n",
+                                  err);
+               len2 = (__u64)msg->data_end - (__u64)msg->data;
+               bpf_printk("sk_msg2: length update %i->%i\n",
+                          len1, len2);
+       }
        bpf_printk("sk_msg2: data length %i err1 %i err2 %i\n",
-                  (__u64)data_end - (__u64)data, err1, err2);
+                  len1, err1, err2);
        return SK_PASS;
 }
 
 SEC("sk_msg3")
 int bpf_prog6(struct sk_msg_md *msg)
 {
-       void *data_end = (void *)(long) msg->data_end;
-       void *data = (void *)(long) msg->data;
-       int *bytes, zero = 0;
+       int *bytes, zero = 0, one = 1;
+       int *start, *end;
 
        bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
        if (bytes)
@@ -179,15 +206,18 @@ int bpf_prog6(struct sk_msg_md *msg)
        bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
        if (bytes)
                bpf_msg_cork_bytes(msg, *bytes);
+       start = bpf_map_lookup_elem(&sock_pull_bytes, &zero);
+       end = bpf_map_lookup_elem(&sock_pull_bytes, &one);
+       if (start && end)
+               bpf_msg_pull_data(msg, *start, *end, 0);
        return bpf_msg_redirect_map(msg, &sock_map_redir, zero, 0);
 }
 
 SEC("sk_msg4")
 int bpf_prog7(struct sk_msg_md *msg)
 {
-       void *data_end = (void *)(long) msg->data_end;
-       void *data = (void *)(long) msg->data;
-       int *bytes, err1 = 0, err2 = 0, zero = 0;
+       int err1 = 0, err2 = 0, zero = 0, one = 1;
+       int *bytes, *start, *end, len1, len2;
 
        bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
        if (bytes)
@@ -195,9 +225,24 @@ int bpf_prog7(struct sk_msg_md *msg)
        bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
        if (bytes)
                err2 = bpf_msg_cork_bytes(msg, *bytes);
-
+       len1 = (__u64)msg->data_end - (__u64)msg->data;
+       start = bpf_map_lookup_elem(&sock_pull_bytes, &zero);
+       end = bpf_map_lookup_elem(&sock_pull_bytes, &one);
+       if (start && end) {
+               int err;
+
+               bpf_printk("sk_msg2: pull(%i:%i)\n",
+                          start ? *start : 0, end ? *end : 0);
+               err = bpf_msg_pull_data(msg, *start, *end, 0);
+               if (err)
+                       bpf_printk("sk_msg2: pull_data err %i\n",
+                                  err);
+               len2 = (__u64)msg->data_end - (__u64)msg->data;
+               bpf_printk("sk_msg2: length update %i->%i\n",
+                          len1, len2);
+       }
        bpf_printk("sk_msg3: redirect(%iB) err1=%i err2=%i\n",
-                  (__u64)data_end - (__u64)data, err1, err2);
+                  len1, err1, err2);
        return bpf_msg_redirect_map(msg, &sock_map_redir, zero, 0);
 }
 
@@ -239,7 +284,8 @@ int bpf_prog9(struct sk_msg_md *msg)
 SEC("sk_msg7")
 int bpf_prog10(struct sk_msg_md *msg)
 {
-       int *bytes, zero = 0;
+       int *bytes, zero = 0, one = 1;
+       int *start, *end;
 
        bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
        if (bytes)
@@ -247,6 +293,11 @@ int bpf_prog10(struct sk_msg_md *msg)
        bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
        if (bytes)
                bpf_msg_cork_bytes(msg, *bytes);
+       start = bpf_map_lookup_elem(&sock_pull_bytes, &zero);
+       end = bpf_map_lookup_elem(&sock_pull_bytes, &one);
+       if (start && end)
+               bpf_msg_pull_data(msg, *start, *end, 0);
+
        return SK_DROP;
 }
 

diff --git a/samples/sockmap/sockmap_user.c b/samples/sockmap/sockmap_user.c
index 52c4ed7774d4d51fc657aba09c744271bea9e2e1..07aa237221d12c46bf3f07e5cb17cb7aebe9a4c3 100644 (file)
--- a/samples/sockmap/sockmap_user.c
+++ b/samples/sockmap/sockmap_user.c
@@ -62,6 +62,8 @@ int txmsg_redir_noisy;
 int txmsg_drop;
 int txmsg_apply;
 int txmsg_cork;
+int txmsg_start;
+int txmsg_end;
 
 static const struct option long_options[] = {
        {"help",        no_argument,            NULL, 'h' },
@@ -79,6 +81,8 @@ static const struct option long_options[] = {
        {"txmsg_drop",          no_argument,    &txmsg_drop, 1 },
        {"txmsg_apply", required_argument,      NULL, 'a'},
        {"txmsg_cork",  required_argument,      NULL, 'k'},
+       {"txmsg_start", required_argument,      NULL, 's'},
+       {"txmsg_end",   required_argument,      NULL, 'e'},
        {0, 0, NULL, 0 }
 };
 
@@ -572,6 +576,12 @@ int main(int argc, char **argv)
        while ((opt = getopt_long(argc, argv, ":dhvc:r:i:l:t:",
                                  long_options, &longindex)) != -1) {
                switch (opt) {
+               case 's':
+                       txmsg_start = atoi(optarg);
+                       break;
+               case 'e':
+                       txmsg_end = atoi(optarg);
+                       break;
                case 'a':
                        txmsg_apply = atoi(optarg);
                        break;
@@ -761,6 +771,28 @@ run:
                        }
                }
 
+               if (txmsg_start) {
+                       err = bpf_map_update_elem(map_fd[5],
+                                                 &i, &txmsg_start, BPF_ANY);
+                       if (err) {
+                               fprintf(stderr,
+                                       "ERROR: bpf_map_update_elem (txmsg_start):  %d (%s)\n",
+                                       err, strerror(errno));
+                               return err;
+                       }
+               }
+
+               if (txmsg_end) {
+                       i = 1;
+                       err = bpf_map_update_elem(map_fd[5],
+                                                 &i, &txmsg_end, BPF_ANY);
+                       if (err) {
+                               fprintf(stderr,
+                                       "ERROR: bpf_map_update_elem (txmsg_end):  %d (%s)\n",
+                                       err, strerror(errno));
+                               return err;
+                       }
+               }
        }
 
        if (txmsg_drop)

diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index e6924ab20fc359461c87648be066aef18da55d0a..d245c41213ac20850a1b9b58f1925b827899ff04 100644 (file)
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -793,7 +793,8 @@ union bpf_attr {
        FN(sock_ops_cb_flags_set),      \
        FN(msg_redirect_map),           \
        FN(msg_apply_bytes),            \
-       FN(msg_cork_bytes),
+       FN(msg_cork_bytes),             \
+       FN(msg_pull_data),
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
  * function eBPF program intends to call

diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
index b5b45ff705fffa68f02de67b4608a846321e05d4..7cae376d8d0c76c556dee7e6ce3c2a2de448a16e 100644 (file)
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -92,6 +92,8 @@ static int (*bpf_msg_apply_bytes)(void *ctx, int len) =
        (void *) BPF_FUNC_msg_apply_bytes;
 static int (*bpf_msg_cork_bytes)(void *ctx, int len) =
        (void *) BPF_FUNC_msg_cork_bytes;
+static int (*bpf_msg_pull_data)(void *ctx, int start, int end, int flags) =
+       (void *) BPF_FUNC_msg_pull_data;
 
 /* llvm builtin functions that eBPF C program may use to
  * emit BPF_LD_ABS and BPF_LD_IND instructions