xref: /freebsd/crypto/openssl/test/helpers/pktsplitbio.c (revision e7be843b4a162e68651d3911f0357ed464915629)
1 /*
2  * Copyright 2023-2025 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the Apache License 2.0 (the "License").  You may not use
5  * this file except in compliance with the License.  You can obtain a copy
6  * in the file LICENSE in the source distribution or at
7  * https://www.openssl.org/source/license.html
8  */
9 
10 #include <openssl/bio.h>
11 #include "quictestlib.h"
12 #include "../testutil.h"
13 
pkt_split_dgram_ctrl(BIO * bio,int cmd,long num,void * ptr)14 static long pkt_split_dgram_ctrl(BIO *bio, int cmd, long num, void *ptr)
15 {
16     long ret;
17     BIO *next = BIO_next(bio);
18 
19     if (next == NULL)
20         return 0;
21 
22     switch (cmd) {
23     case BIO_CTRL_DUP:
24         ret = 0L;
25         break;
26     default:
27         ret = BIO_ctrl(next, cmd, num, ptr);
28         break;
29     }
30     return ret;
31 }
32 
pkt_split_dgram_sendmmsg(BIO * bio,BIO_MSG * msg,size_t stride,size_t num_msg,uint64_t flags,size_t * msgs_processed)33 static int pkt_split_dgram_sendmmsg(BIO *bio, BIO_MSG *msg, size_t stride,
34                                     size_t num_msg, uint64_t flags,
35                                     size_t *msgs_processed)
36 {
37     BIO *next = BIO_next(bio);
38 
39     if (next == NULL)
40         return 0;
41 
42     /*
43      * We only introduce noise when receiving messages. We just pass this on
44      * to the underlying BIO.
45      */
46     return BIO_sendmmsg(next, msg, stride, num_msg, flags, msgs_processed);
47 }
48 
pkt_split_dgram_recvmmsg(BIO * bio,BIO_MSG * msg,size_t stride,size_t num_msg,uint64_t flags,size_t * msgs_processed)49 static int pkt_split_dgram_recvmmsg(BIO *bio, BIO_MSG *msg, size_t stride,
50                                     size_t num_msg, uint64_t flags,
51                                     size_t *msgs_processed)
52 {
53     BIO *next = BIO_next(bio);
54     size_t i, j, data_len = 0, msg_cnt = 0;
55     BIO_MSG *thismsg;
56     QTEST_DATA *bdata = BIO_get_data(bio);
57 
58     if (!TEST_ptr(next) || !TEST_ptr(bdata))
59         return 0;
60 
61     /*
62      * For simplicity we assume that all elements in the msg array have the
63      * same data_len. They are not required to by the API, but it would be quite
64      * strange for that not to be the case - and our code that calls
65      * BIO_recvmmsg does do this (which is all that is important for this test
66      * code). We test the invariant here.
67      */
68     for (i = 0; i < num_msg; i++) {
69         if (i == 0)
70             data_len = msg[i].data_len;
71         else if (!TEST_size_t_eq(msg[i].data_len, data_len))
72             return 0;
73     }
74 
75     if (!BIO_recvmmsg(next, msg, stride, num_msg, flags, msgs_processed))
76         return 0;
77 
78     msg_cnt = *msgs_processed;
79     if (msg_cnt == num_msg)
80         return 1; /* We've used all our slots and can't split any more */
81     assert(msg_cnt < num_msg);
82 
83     for (i = 0, thismsg = msg; i < msg_cnt; i++, thismsg++) {
84         QUIC_PKT_HDR hdr;
85         PACKET pkt;
86         size_t remain;
87 
88         if (!PACKET_buf_init(&pkt, thismsg->data, thismsg->data_len))
89             return 0;
90 
91         /* Decode the packet header */
92         if (ossl_quic_wire_decode_pkt_hdr(&pkt, bdata->short_conn_id_len,
93                                           0, 0, &hdr, NULL, NULL) != 1)
94             return 0;
95         remain = PACKET_remaining(&pkt);
96         if (remain > 0) {
97             for (j = msg_cnt; j > i; j--) {
98                 if (!bio_msg_copy(&msg[j], &msg[j - 1]))
99                     return 0;
100             }
101             thismsg->data_len -= remain;
102             msg[i + 1].data_len = remain;
103             memmove(msg[i + 1].data,
104                     (unsigned char *)msg[i + 1].data + thismsg->data_len,
105                     remain);
106             msg_cnt++;
107         }
108     }
109 
110     *msgs_processed = msg_cnt;
111     return 1;
112 }
113 
114 /* Choose a sufficiently large type likely to be unused for this custom BIO */
115 #define BIO_TYPE_PKT_SPLIT_DGRAM_FILTER  (0x81 | BIO_TYPE_FILTER)
116 
117 static BIO_METHOD *method_pkt_split_dgram = NULL;
118 
119 /* Note: Not thread safe! */
bio_f_pkt_split_dgram_filter(void)120 const BIO_METHOD *bio_f_pkt_split_dgram_filter(void)
121 {
122     if (method_pkt_split_dgram == NULL) {
123         method_pkt_split_dgram = BIO_meth_new(BIO_TYPE_PKT_SPLIT_DGRAM_FILTER,
124                                               "Packet splitting datagram filter");
125         if (method_pkt_split_dgram == NULL
126             || !BIO_meth_set_ctrl(method_pkt_split_dgram, pkt_split_dgram_ctrl)
127             || !BIO_meth_set_sendmmsg(method_pkt_split_dgram,
128                                       pkt_split_dgram_sendmmsg)
129             || !BIO_meth_set_recvmmsg(method_pkt_split_dgram,
130                                       pkt_split_dgram_recvmmsg))
131             return NULL;
132     }
133     return method_pkt_split_dgram;
134 }
135 
bio_f_pkt_split_dgram_filter_free(void)136 void bio_f_pkt_split_dgram_filter_free(void)
137 {
138     BIO_meth_free(method_pkt_split_dgram);
139 }
140