[VPP-1719] Policy based ipsec failing.

[vvalderrv]

Recent changes in master (post stable/1904) seem to have broken policy based ipsec (i.e., no explicit tunnel interface configured). This configuration/test case works in 1904.

A ping is done from the host side of node1 (source ip will be 192.168.30.166 routed to VPP interface 192.168.30.66) to 192.168.32.67 (which should be encapsulated in ipsec to node2.

The backtrace looks like this (with some debug printfs I added, seems to maybe be looping?):

Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:223: ipsec_output_inline: START: packet received current_data 0 -pre_data_size -128
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:231: ipsec_output_inline: packet received from 192.168.30.166 to 192.168.32.67
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:234: ipsec_output_inline: last_sw_if_index 4294967295 sw_if_index0 4
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:245: ipsec_output_inline: p 0
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:281: packet received from 192.168.30.166 to 192.168.32.67 port 33505
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:283: sw_if_index0 4 spd_index0 0 spd_id 1
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:399: ipsec_output_inline: END next_node_index dpdk-esp4-encrypt (197)
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:223: ipsec_output_inline: START: packet received current_data -44 -pre_data_size -128
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:231: ipsec_output_inline: packet received from 192.168.25.66 to 192.168.25.67
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:234: ipsec_output_inline: last_sw_if_index 4294967295 sw_if_index0 4
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:245: ipsec_output_inline: p 0
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:281: packet received from 192.168.25.66 to 192.168.25.67 port 2030
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:283: sw_if_index0 4 spd_index0 0 spd_id 1
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:399: ipsec_output_inline: END next_node_index dpdk-esp4-encrypt (197)
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:223: ipsec_output_inline: START: packet received current_data -88 -pre_data_size -128
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:231: ipsec_output_inline: packet received from 192.168.25.66 to 192.168.25.67
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:234: ipsec_output_inline: last_sw_if_index 4294967295 sw_if_index0 4
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:245: ipsec_output_inline: p 0
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:281: packet received from 192.168.25.66 to 192.168.25.67 port 2030
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:283: sw_if_index0 4 spd_index0 0 spd_id 1
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:399: ipsec_output_inline: END next_node_index dpdk-esp4-encrypt (197)
Jul 09 13:46:02 dpdk2 vnet[2968]: ipsec_output_inline:223: ipsec_output_inline: START: packet received current_data -132 -pre_data_size -128
Jul 09 13:46:02 dpdk2 vnet[2968]: /home/chopps/net/w/vpp/src/vlib/buffer.h:232 (vlib_buffer_get_current) assertion `(signed) b->current_data >= (signed) -VLIB_BUFFER_PRE_DATA_SIZE' fails
Jul 09 13:46:02 dpdk2 vnet[2968]: received signal SIGABRT, PC 0x7fcaf32cee97
Jul 09 13:46:02 dpdk2 vnet[2968]: #0 0x00007fcaf3c98c73 unix_signal_handler + 0x25b
Jul 09 13:46:02 dpdk2 vnet[2968]: #1 0x00007fcaf39a6890 0x7fcaf39a6890
Jul 09 13:46:02 dpdk2 vnet[2968]: #2 0x00007fcaf32cee97 gsignal + 0xc7
Jul 09 13:46:02 dpdk2 vnet[2968]: #3 0x00007fcaf32d0801 abort + 0x141
Jul 09 13:46:02 dpdk2 vnet[2968]: #4 0x00005647559dd05d 0x5647559dd05d
Jul 09 13:46:02 dpdk2 vnet[2968]: #5 0x00007fcaf36b4d53 debugger + 0x9
Jul 09 13:46:02 dpdk2 vnet[2968]: #6 0x00007fcaf36b5122 _clib_error + 0x2c0
Jul 09 13:46:02 dpdk2 vnet[2968]: #7 0x00007fcaf48ad611 vlib_buffer_get_current + 0x56
Jul 09 13:46:02 dpdk2 vnet[2968]: #8 0x00007fcaf48aec70 ipsec_output_inline + 0x221
Jul 09 13:46:02 dpdk2 vnet[2968]: #9 0x00007fcaf48af995 ipsec4_output_node_fn + 0x2d
Jul 09 13:46:02 dpdk2 vnet[2968]: #10 0x00007fcaf3c3138c dispatch_node + 0x328
Jul 09 13:46:02 dpdk2 vnet[2968]: #11 0x00007fcaf3c31b44 dispatch_pending_node + 0x363
Jul 09 13:46:02 dpdk2 vnet[2968]: #12 0x00007fcaf3c337c4 vlib_main_or_worker_loop + 0xa31
Jul 09 13:46:02 dpdk2 vnet[2968]: #13 0x00007fcaf3c34027 vlib_main_loop + 0x1d
Jul 09 13:46:02 dpdk2 vnet[2968]: #14 0x00007fcaf3c34c3e vlib_main + 0x931