pespin has submitted this change. ( https://gerrit.osmocom.org/c/osmo-pcap/+/39170?usp=email )
Change subject: pcap-client: Decouple dev capture handling from client ......................................................................
pcap-client: Decouple dev capture handling from client
A new struct osmo_pcap_handle is introduced, and struct osmo_pcap_client manages a list of it. This is a first step towards supporting capturing from multiple interfaces. VTY still enforces only 1 configured interface since further work is required.
Related: SYS#5822 Change-Id: I02f33f11cbcb7ed5ff6475df9442741618178379 --- M include/osmo-pcap/osmo_pcap_client.h M src/osmo_client_core.c M src/osmo_client_main.c M src/osmo_client_network.c M src/osmo_client_vty.c 5 files changed, 192 insertions(+), 104 deletions(-)
Approvals: laforge: Looks good to me, but someone else must approve fixeria: Looks good to me, approved Jenkins Builder: Verified
diff --git a/include/osmo-pcap/osmo_pcap_client.h b/include/osmo-pcap/osmo_pcap_client.h index ce2fb8f..6725201 100644 --- a/include/osmo-pcap/osmo_pcap_client.h +++ b/include/osmo-pcap/osmo_pcap_client.h @@ -82,22 +82,26 @@ struct osmo_pcap_client *client; };
-struct osmo_pcap_client { - char *device; +struct osmo_pcap_handle { + struct llist_head entry; /* item in (struct osmo_pcap_client)->handles */ + struct osmo_pcap_client *client; /* back pointer */ + char *devname; pcap_t *handle; - char errbuf[PCAP_ERRBUF_SIZE]; - + struct osmo_fd fd; u_int last_ps_recv; u_int last_ps_drop; u_int last_ps_ifdrop; struct osmo_timer_list pcap_stat_timer; - struct bpf_program bpf; - char *filter_string; +}; + +struct osmo_pcap_client { + struct llist_head handles; /* list of struct osmo_pcap_handle */ + + char *filter_string; int filter_itself; int gprs_filtering; int snaplen; - struct osmo_fd fd;
struct osmo_pcap_client_conn *conn; struct llist_head conns; @@ -111,12 +115,14 @@ struct osmo_pcap_client *osmo_pcap_client_alloc(void *tall_ctx); int vty_client_init(void);
-int osmo_client_capture(struct osmo_pcap_client *client, const char *device); +int osmo_client_start_capture(struct osmo_pcap_client *client); int osmo_client_filter(struct osmo_pcap_client *client, const char *filter);
struct osmo_pcap_client_conn *osmo_client_find_or_create_conn(struct osmo_pcap_client *, const char *name); struct osmo_pcap_client_conn *osmo_client_find_conn(struct osmo_pcap_client *, const char *name);
+struct osmo_pcap_handle *osmo_client_find_handle(struct osmo_pcap_client *client, const char *devname); + struct osmo_pcap_client_conn *osmo_client_conn_alloc(struct osmo_pcap_client *client, const char *name); void osmo_client_conn_free(struct osmo_pcap_client_conn *conn); void osmo_client_conn_send_data(struct osmo_pcap_client_conn *conn, @@ -125,3 +131,8 @@ void osmo_client_conn_connect(struct osmo_pcap_client_conn *conn); void osmo_client_conn_disconnect(struct osmo_pcap_client_conn *conn); void osmo_client_conn_reconnect(struct osmo_pcap_client_conn *conn); + + +struct osmo_pcap_handle *osmo_pcap_handle_alloc(struct osmo_pcap_client *client, const char *devname); +void osmo_pcap_handle_free(struct osmo_pcap_handle *ph); +int osmo_pcap_handle_start_capture(struct osmo_pcap_handle *ph); diff --git a/src/osmo_client_core.c b/src/osmo_client_core.c index 41f4dfc..009362c 100644 --- a/src/osmo_client_core.c +++ b/src/osmo_client_core.c @@ -102,6 +102,7 @@
static int can_forward_packet( struct osmo_pcap_client *client, + struct osmo_pcap_handle *ph, struct pcap_pkthdr *hdr, const u_char *data) { @@ -116,7 +117,7 @@ if (!client->gprs_filtering) return 1;
- ll_type = pcap_datalink(client->handle); + ll_type = pcap_datalink(ph->handle); switch (ll_type) { case DLT_EN10MB: offset = 14; @@ -154,18 +155,19 @@
static int pcap_read_cb(struct osmo_fd *fd, unsigned int what) { - struct osmo_pcap_client *client = fd->data; + struct osmo_pcap_handle *ph = fd->data; + struct osmo_pcap_client *client = ph->client; struct osmo_pcap_client_conn *conn; struct pcap_pkthdr hdr; const u_char *data;
- data = pcap_next(client->handle, &hdr); + data = pcap_next(ph->handle, &hdr); if (!data) { rate_ctr_inc(rate_ctr_group_get_ctr(client->ctrg, CLIENT_CTR_PERR)); return -1; }
- if (!can_forward_packet(client, &hdr, data)) + if (!can_forward_packet(client, ph, &hdr, data)) return 0;
llist_for_each_entry(conn, &client->conns, entry) @@ -207,138 +209,90 @@ *old_val = new_val; }
-static void pcap_check_stats_cb(void *_client) +static void pcap_check_stats_cb(void *_ph) { struct pcap_stat stat; - struct osmo_pcap_client *client = _client; + struct osmo_pcap_handle *ph = _ph; + struct osmo_pcap_client *client = ph->client; int rc;
/* reschedule */ - osmo_timer_schedule(&client->pcap_stat_timer, 10, 0); + osmo_timer_schedule(&ph->pcap_stat_timer, 10, 0);
memset(&stat, 0, sizeof(stat)); - rc = pcap_stats(client->handle, &stat); + rc = pcap_stats(ph->handle, &stat); if (rc != 0) { LOGP(DCLIENT, LOGL_ERROR, "Failed to query pcap stats: %s\n", - pcap_geterr(client->handle)); + pcap_geterr(ph->handle)); rate_ctr_inc(rate_ctr_group_get_ctr(client->ctrg, CLIENT_CTR_PERR)); return; }
- add_psbl_wrapped_ctr(client, &client->last_ps_recv, stat.ps_recv, CLIENT_CTR_P_RECV); - add_psbl_wrapped_ctr(client, &client->last_ps_drop, stat.ps_drop, CLIENT_CTR_P_DROP); - add_psbl_wrapped_ctr(client, &client->last_ps_ifdrop, stat.ps_ifdrop, CLIENT_CTR_P_IFDROP); + add_psbl_wrapped_ctr(client, &ph->last_ps_recv, stat.ps_recv, CLIENT_CTR_P_RECV); + add_psbl_wrapped_ctr(client, &ph->last_ps_drop, stat.ps_drop, CLIENT_CTR_P_DROP); + add_psbl_wrapped_ctr(client, &ph->last_ps_ifdrop, stat.ps_ifdrop, CLIENT_CTR_P_IFDROP); }
-static int osmo_install_filter(struct osmo_pcap_client *client) +static int osmo_pcap_handle_install_filter(struct osmo_pcap_handle *ph) { int rc; - pcap_freecode(&client->bpf); + pcap_freecode(&ph->bpf);
- if (!client->handle) { + if (!ph->handle) { LOGP(DCLIENT, LOGL_NOTICE, "Filter will only be applied later.\n"); - return 1; + return 0; }
- rc = pcap_compile(client->handle, &client->bpf, - client->filter_string, 1, PCAP_NETMASK_UNKNOWN); + rc = pcap_compile(ph->handle, &ph->bpf, + ph->client->filter_string, 1, PCAP_NETMASK_UNKNOWN); if (rc != 0) { LOGP(DCLIENT, LOGL_ERROR, "Failed to compile the filter: %s\n", - pcap_geterr(client->handle)); + pcap_geterr(ph->handle)); return rc; }
- rc = pcap_setfilter(client->handle, &client->bpf); + rc = pcap_setfilter(ph->handle, &ph->bpf); if (rc != 0) { LOGP(DCLIENT, LOGL_ERROR, "Failed to set the filter on the interface: %s\n", - pcap_geterr(client->handle)); - pcap_freecode(&client->bpf); + pcap_geterr(ph->handle)); + pcap_freecode(&ph->bpf); return rc; }
return rc; }
-static void free_all(struct osmo_pcap_client *client) +int osmo_client_start_capture(struct osmo_pcap_client *client) { - if (!client->handle) - return; - - pcap_freecode(&client->bpf); - - if (client->fd.fd >= 0) { - osmo_fd_unregister(&client->fd); - client->fd.fd = -1; - } - - pcap_close(client->handle); - osmo_timer_del(&client->pcap_stat_timer); - client->handle = NULL; -} - -int osmo_client_capture(struct osmo_pcap_client *client, const char *device) -{ + struct osmo_pcap_handle *ph; struct osmo_pcap_client_conn *conn; - int fd; + int rc;
- talloc_free(client->device); - free_all(client); - - client->device = talloc_strdup(client, device); - if (!client->device) { - LOGP(DCLIENT, LOGL_ERROR, "Failed to copy string.\n"); - return 1; + llist_for_each_entry(ph, &client->handles, entry) { + rc = osmo_pcap_handle_start_capture(ph); + if (rc < 0) + return rc; }
- LOGP(DCLIENT, LOGL_INFO, "Opening device %s for capture with snaplen %zu\n", - client->device, (size_t) client->snaplen); - client->handle = pcap_open_live(client->device, client->snaplen, 0, - 1000, client->errbuf); - if (!client->handle) { - LOGP(DCLIENT, LOGL_ERROR, - "Failed to open the device: %s\n", client->errbuf); - return 2; - } - - fd = pcap_fileno(client->handle); - if (fd == -1) { - LOGP(DCLIENT, LOGL_ERROR, - "No file descriptor provided.\n"); - free_all(client); - return 3; - } - - osmo_fd_setup(&client->fd, fd, OSMO_FD_READ, pcap_read_cb, client, 0); - if (osmo_fd_register(&client->fd) != 0) { - LOGP(DCLIENT, LOGL_ERROR, - "Failed to register the fd.\n"); - client->fd.fd = -1; - free_all(client); - return 4; - } - - client->pcap_stat_timer.data = client; - client->pcap_stat_timer.cb = pcap_check_stats_cb; - pcap_check_stats_cb(client); - llist_for_each_entry(conn, &client->conns, entry) osmo_client_conn_send_link(conn); - - if (client->filter_string) { - osmo_install_filter(client); - } - return 0; }
int osmo_client_filter(struct osmo_pcap_client *client, const char *filter) { + struct osmo_pcap_handle *ph; + int rc = 0; talloc_free(client->filter_string); client->filter_string = talloc_strdup(client, filter); - return osmo_install_filter(client); + + llist_for_each_entry(ph, &client->handles, entry) + rc |= osmo_pcap_handle_install_filter(ph); + + return rc; }
struct osmo_pcap_client *osmo_pcap_client_alloc(void *tall_ctx) @@ -348,8 +302,8 @@ if (!client) return NULL;
- client->fd.fd = -1; client->snaplen = DEFAULT_SNAPLEN; + INIT_LLIST_HEAD(&client->handles); INIT_LLIST_HEAD(&client->conns);
return client; @@ -407,3 +361,89 @@ conn = osmo_client_conn_alloc(client, name); return conn; } + +struct osmo_pcap_handle *osmo_client_find_handle(struct osmo_pcap_client *client, const char *devname) +{ + struct osmo_pcap_handle *ph; + + llist_for_each_entry(ph, &client->handles, entry) + if (strcmp(ph->devname, devname) == 0) + return ph; + return NULL; +} + +struct osmo_pcap_handle *osmo_pcap_handle_alloc(struct osmo_pcap_client *client, const char *devname) +{ + struct osmo_pcap_handle *ph; + + ph = talloc_zero(client, struct osmo_pcap_handle); + OSMO_ASSERT(ph); + + ph->devname = talloc_strdup(ph, devname); + OSMO_ASSERT(ph->devname); + + ph->client = client; + ph->fd.fd = -1; + + llist_add_tail(&ph->entry, &client->handles); + return ph; +} + +void osmo_pcap_handle_free(struct osmo_pcap_handle *ph) +{ + if (!ph) + return; + llist_del(&ph->entry); + + osmo_timer_del(&ph->pcap_stat_timer); + + pcap_freecode(&ph->bpf); + + if (ph->fd.fd >= 0) { + osmo_fd_unregister(&ph->fd); + ph->fd.fd = -1; + } + + if (ph->handle) { + pcap_close(ph->handle); + ph->handle = NULL; + } + + talloc_free(ph); +} + +int osmo_pcap_handle_start_capture(struct osmo_pcap_handle *ph) +{ + struct osmo_pcap_client *client = ph->client; + int fd; + char errbuf[PCAP_ERRBUF_SIZE]; + + LOGP(DCLIENT, LOGL_INFO, "Opening device %s for capture with snaplen %zu\n", + ph->devname, (size_t) client->snaplen); + ph->handle = pcap_open_live(ph->devname, client->snaplen, 0, 1000, errbuf); + if (!ph->handle) { + LOGP(DCLIENT, LOGL_ERROR, + "Failed to open the device: %s\n", errbuf); + return -2; + } + + fd = pcap_fileno(ph->handle); + if (fd == -1) { + LOGP(DCLIENT, LOGL_ERROR, "No file descriptor provided.\n"); + return -3; + } + + osmo_fd_setup(&ph->fd, fd, OSMO_FD_READ, pcap_read_cb, ph, 0); + if (osmo_fd_register(&ph->fd) != 0) { + LOGP(DCLIENT, LOGL_ERROR, + "Failed to register the fd.\n"); + return -4; + } + + osmo_timer_setup(&ph->pcap_stat_timer, pcap_check_stats_cb, ph); + pcap_check_stats_cb(ph); + + if (client->filter_string) + osmo_pcap_handle_install_filter(ph); + return 0; +} diff --git a/src/osmo_client_main.c b/src/osmo_client_main.c index c7af965..3fa0ae4 100644 --- a/src/osmo_client_main.c +++ b/src/osmo_client_main.c @@ -283,6 +283,11 @@ exit(1); }
+ rc = osmo_client_start_capture(pcap_client); + if (rc < 0) { + LOGP(DCLIENT, LOGL_ERROR, "Failed to start capturing on interfaces\n"); + exit(1); + }
/* attempt to connect to the remote */ if (pcap_client->conn->srv_ip && pcap_client->conn->srv_port > 0) diff --git a/src/osmo_client_network.c b/src/osmo_client_network.c index 52246d4..e27a91f 100644 --- a/src/osmo_client_network.c +++ b/src/osmo_client_network.c @@ -169,6 +169,7 @@ struct osmo_pcap_pkthdr *hdr; struct msgb *msg; int offset, ip_len; + struct osmo_pcap_handle *ph;
if (in_hdr->len > in_hdr->caplen) { LOGP(DCLIENT, LOGL_ERROR, @@ -204,7 +205,13 @@ rate_ctr_inc(rate_ctr_group_get_ctr(conn->client->ctrg, CLIENT_CTR_PKTS)); break; case PROTOCOL_IPIP: - offset = get_iphdr_offset(pcap_datalink(conn->client->handle)); + /* TODO: support capturing from multiple interfaces here: */ + ph = llist_first_entry_or_null(&conn->client->handles, struct osmo_pcap_handle, entry); + if (!ph) { + msgb_free(msg); + return; + } + offset = get_iphdr_offset(pcap_datalink(ph->handle)); if (offset < 0) { msgb_free(msg); return; @@ -226,6 +233,7 @@
void osmo_client_conn_send_link(struct osmo_pcap_client_conn *conn) { + struct osmo_pcap_handle *ph; struct pcap_file_header *hdr; struct osmo_pcap_data *om_hdr; struct msgb *msg; @@ -234,7 +242,9 @@ if (conn->protocol == PROTOCOL_IPIP) return;
- if (!conn->client->handle) { + /* TODO: support capturing from multiple interfaces here: */ + ph = llist_first_entry_or_null(&conn->client->handles, struct osmo_pcap_handle, entry); + if (!ph || !ph->handle) { LOGP(DCLIENT, LOGL_ERROR, "No pcap_handle not sending link info to conn=%s\n", conn->name); return; @@ -258,7 +268,7 @@ hdr->thiszone = 0; hdr->sigfigs = 0; hdr->snaplen = conn->client->snaplen; - hdr->linktype = pcap_datalink(conn->client->handle); + hdr->linktype = pcap_datalink(ph->handle);
write_data(conn, msg); } diff --git a/src/osmo_client_vty.c b/src/osmo_client_vty.c index 84f7e05..c976a1a 100644 --- a/src/osmo_client_vty.c +++ b/src/osmo_client_vty.c @@ -126,11 +126,14 @@
static int config_write_client(struct vty *vty) { + struct osmo_pcap_handle *ph; + vty_out(vty, "client%s", VTY_NEWLINE);
- if (pcap_client->device) + llist_for_each_entry(ph, &pcap_client->handles, entry) { vty_out(vty, " pcap device %s%s", - pcap_client->device, VTY_NEWLINE); + ph->devname, VTY_NEWLINE); + } if (pcap_client->snaplen != DEFAULT_SNAPLEN) vty_out(vty, " pcap snaplen %d%s", pcap_client->snaplen, VTY_NEWLINE); @@ -147,12 +150,34 @@ return CMD_SUCCESS; }
+DEFUN(cfg_client_no_device, + cfg_client_no_device_cmd, + "no pcap device NAME", + NO_STR PCAP_STRING "the device to filter\n" "device name\n") +{ + struct osmo_pcap_handle *ph = osmo_client_find_handle(pcap_client, argv[0]); + if (!ph) { + vty_out(vty, "%% Device %s not found!%s", argv[0], VTY_NEWLINE); + return CMD_WARNING; + } + osmo_pcap_handle_free(ph); + return CMD_SUCCESS; +} + DEFUN(cfg_client_device, cfg_client_device_cmd, "pcap device NAME", PCAP_STRING "the device to filter\n" "device name\n") { - osmo_client_capture(pcap_client, argv[0]); + struct osmo_pcap_handle *ph = osmo_client_find_handle(pcap_client, argv[0]); + if (!ph) { + /* Only allow max one for now:*/ + if (llist_count(&pcap_client->handles) > 0) { + vty_out(vty, "Only one 'pcap device' allowed! Remove the old one with 'no pcap device' first!%s", VTY_NEWLINE); + return CMD_WARNING; + } + osmo_pcap_handle_alloc(pcap_client, argv[0]); + } return CMD_SUCCESS; }
@@ -161,10 +186,6 @@ "pcap snaplen <1-262144>", /* MAXIMUM_SNAPLEN */ PCAP_STRING "snapshot length\n" "Bytes\n") { - if (pcap_client->handle) { - vty_out(vty, "'pcap snaplen' must be set before 'pcap device' to take effect!%s", VTY_NEWLINE); - return CMD_WARNING; - } pcap_client->snaplen = atoi(argv[0]); return CMD_SUCCESS; } @@ -544,6 +565,7 @@
install_node(&server_node, config_write_server);
+ install_element(CLIENT_NODE, &cfg_client_no_device_cmd); install_element(CLIENT_NODE, &cfg_client_device_cmd); install_element(CLIENT_NODE, &cfg_client_snaplen_cmd); install_element(CLIENT_NODE, &cfg_client_filter_cmd);
-
pespin