xref: /openbmc/libpldm/src/requester/pldm.c (revision 9d2a1c6ad095d0b04d1c39a794487eafda1f34fb)
1 #include "config.h"
2 #include "libpldm/requester/pldm.h"
3 #include "base.h"
4 #include "libpldm/transport.h"
5 
6 #include <bits/types/struct_iovec.h>
7 #include <stdbool.h>
8 #include <stdlib.h>
9 #include <string.h>
10 #include <sys/socket.h>
11 #include <sys/un.h>
12 #include <unistd.h>
13 
14 /* Temporary for old api */
15 #include "libpldm/transport/mctp-demux.h"
16 extern int
17 pldm_transport_mctp_demux_get_socket_fd(struct pldm_transport_mctp_demux *ctx);
18 extern struct pldm_transport_mctp_demux *
19 pldm_transport_mctp_demux_init_with_fd(int mctp_fd);
20 
21 /* ---  old APIS written in terms of the new API -- */
22 /*
23  * pldm_open returns the file descriptor to the MCTP socket, which needs to
24  * persist over api calls (so a consumer can poll it for incoming messages).
25  * So we need a global variable to store the transport struct
26  */
27 static struct pldm_transport_mctp_demux *open_transport;
28 
29 LIBPLDM_ABI_STABLE
30 pldm_requester_rc_t pldm_open(void)
31 {
32 	int fd;
33 	int rc;
34 
35 	if (open_transport) {
36 		fd = pldm_transport_mctp_demux_get_socket_fd(open_transport);
37 		return fd;
38 	}
39 
40 	struct pldm_transport_mctp_demux *demux = NULL;
41 	rc = pldm_transport_mctp_demux_init(&demux);
42 	if (rc) {
43 		return rc;
44 	}
45 
46 	fd = pldm_transport_mctp_demux_get_socket_fd(demux);
47 
48 	open_transport = demux;
49 
50 	return fd;
51 }
52 
53 /* This macro does the setup and teardown required for the old API to use the
54  * new API. Since the setup/teardown logic is the same for all four send/recv
55  * functions, it makes sense to only define it once. */
56 #define PLDM_REQ_FN(eid, fd, fn, ...)                                            \
57 	do {                                                                     \
58 		struct pldm_transport_mctp_demux *demux;                         \
59 		bool using_open_transport = false;                               \
60 		pldm_requester_rc_t rc;                                          \
61 		pldm_tid_t tid = 1;                                              \
62 		struct pldm_transport *ctx;                                      \
63 		/* The fd can be for a socket we opened or one the consumer    \
64 		 * opened. */ \
65 		if (open_transport &&                                            \
66 		    mctp_fd == pldm_transport_mctp_demux_get_socket_fd(          \
67 				       open_transport)) {                        \
68 			using_open_transport = true;                             \
69 			demux = open_transport;                                  \
70 		} else {                                                         \
71 			demux = pldm_transport_mctp_demux_init_with_fd(fd);      \
72 			if (!demux) {                                            \
73 				rc = PLDM_REQUESTER_OPEN_FAIL;                   \
74 				goto transport_out;                              \
75 			}                                                        \
76 		}                                                                \
77 		ctx = pldm_transport_mctp_demux_core(demux);                     \
78 		rc = pldm_transport_mctp_demux_map_tid(demux, tid, eid);         \
79 		if (rc) {                                                        \
80 			rc = PLDM_REQUESTER_OPEN_FAIL;                           \
81 			goto transport_out;                                      \
82 		}                                                                \
83 		rc = fn(ctx, tid, __VA_ARGS__);                                  \
84 	transport_out:                                                           \
85 		if (!using_open_transport) {                                     \
86 			pldm_transport_mctp_demux_destroy(demux);                \
87 		}                                                                \
88 		return rc;                                                       \
89 	} while (0)
90 
91 LIBPLDM_ABI_STABLE
92 pldm_requester_rc_t pldm_recv_any(mctp_eid_t eid, int mctp_fd,
93 				  uint8_t **pldm_resp_msg, size_t *resp_msg_len)
94 {
95 	PLDM_REQ_FN(eid, mctp_fd, pldm_transport_recv_msg,
96 		    (void **)pldm_resp_msg, resp_msg_len);
97 }
98 
99 LIBPLDM_ABI_STABLE
100 pldm_requester_rc_t pldm_recv(mctp_eid_t eid, int mctp_fd,
101 			      __attribute__((unused)) uint8_t instance_id,
102 			      uint8_t **pldm_resp_msg, size_t *resp_msg_len)
103 {
104 	pldm_requester_rc_t rc =
105 		pldm_recv_any(eid, mctp_fd, pldm_resp_msg, resp_msg_len);
106 	struct pldm_msg_hdr *hdr = (struct pldm_msg_hdr *)(*pldm_resp_msg);
107 	if (hdr->instance_id != instance_id) {
108 		free(*pldm_resp_msg);
109 		*pldm_resp_msg = NULL;
110 		return PLDM_REQUESTER_INSTANCE_ID_MISMATCH;
111 	}
112 	return rc;
113 }
114 
115 LIBPLDM_ABI_STABLE
116 pldm_requester_rc_t pldm_send_recv(mctp_eid_t eid, int mctp_fd,
117 				   const uint8_t *pldm_req_msg,
118 				   size_t req_msg_len, uint8_t **pldm_resp_msg,
119 				   size_t *resp_msg_len)
120 {
121 	PLDM_REQ_FN(eid, mctp_fd, pldm_transport_send_recv_msg, pldm_req_msg,
122 		    req_msg_len, (void **)pldm_resp_msg, resp_msg_len);
123 }
124 
125 LIBPLDM_ABI_STABLE
126 pldm_requester_rc_t pldm_send(mctp_eid_t eid, int mctp_fd,
127 			      const uint8_t *pldm_req_msg, size_t req_msg_len)
128 {
129 	PLDM_REQ_FN(eid, mctp_fd, pldm_transport_send_msg, (void *)pldm_req_msg,
130 		    req_msg_len);
131 }
132 
133 /* Adding this here for completeness in the case we can't smoothly
134  * transition apps over to the new api */
135 LIBPLDM_ABI_STABLE
136 void pldm_close(void)
137 {
138 	if (open_transport) {
139 		pldm_transport_mctp_demux_destroy(open_transport);
140 	}
141 	open_transport = NULL;
142 }
143