1 f024663d 2021-09-05 stsp /*
  2 f024663d 2021-09-05 stsp  * Copyright (c) 2019 Ori Bernstein <ori@openbsd.org>
  3 f024663d 2021-09-05 stsp  * Copyright (c) 2021 Stefan Sperling <stsp@openbsd.org>
  4 f024663d 2021-09-05 stsp  *
  5 f024663d 2021-09-05 stsp  * Permission to use, copy, modify, and distribute this software for any
  6 f024663d 2021-09-05 stsp  * purpose with or without fee is hereby granted, provided that the above
  7 f024663d 2021-09-05 stsp  * copyright notice and this permission notice appear in all copies.
  8 f024663d 2021-09-05 stsp  *
  9 f024663d 2021-09-05 stsp  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 10 f024663d 2021-09-05 stsp  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 11 f024663d 2021-09-05 stsp  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 12 f024663d 2021-09-05 stsp  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 13 f024663d 2021-09-05 stsp  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 14 f024663d 2021-09-05 stsp  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 15 f024663d 2021-09-05 stsp  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 16 f024663d 2021-09-05 stsp  */
 17 f024663d 2021-09-05 stsp 
 18 f024663d 2021-09-05 stsp #include <ctype.h>
 19 f024663d 2021-09-05 stsp #include <errno.h>
 20 f024663d 2021-09-05 stsp #include <limits.h>
 21 f024663d 2021-09-05 stsp #include <stdio.h>
 22 f024663d 2021-09-05 stsp #include <stdlib.h>
 23 f024663d 2021-09-05 stsp #include <unistd.h>
 24 f024663d 2021-09-05 stsp 
 25 f024663d 2021-09-05 stsp #include "got_error.h"
 26 336075a4 2022-06-25 op #include "got_lib_pkt.h"
 27 6fefa431 2024-05-05 stsp #include "got_lib_poll.h"
 28 f024663d 2021-09-05 stsp 
 29 6fefa431 2024-05-05 stsp #define GOT_PKT_TIMEOUT	30
 30 6fefa431 2024-05-05 stsp 
 31 f024663d 2021-09-05 stsp const struct got_error *
 32 f024663d 2021-09-05 stsp got_pkt_readn(ssize_t *off, int fd, void *buf, size_t n)
 33 f024663d 2021-09-05 stsp {
 34 6fefa431 2024-05-05 stsp 	const struct got_error *err;
 35 6fefa431 2024-05-05 stsp 	size_t len;
 36 f024663d 2021-09-05 stsp 
 37 6fefa431 2024-05-05 stsp 	err = got_poll_read_full_timeout(fd, &len, buf, n, n,
 38 6fefa431 2024-05-05 stsp 	    GOT_PKT_TIMEOUT);
 39 6fefa431 2024-05-05 stsp 	if (err)
 40 6fefa431 2024-05-05 stsp 		return err;
 41 6fefa431 2024-05-05 stsp 
 42 6fefa431 2024-05-05 stsp 	/* XXX size_t -> ssize_t */
 43 6fefa431 2024-05-05 stsp 	if (len > SSIZE_MAX)
 44 6fefa431 2024-05-05 stsp 		return got_error(GOT_ERR_RANGE);
 45 6fefa431 2024-05-05 stsp 	*off = len;
 46 f024663d 2021-09-05 stsp 	return NULL;
 47 f024663d 2021-09-05 stsp }
 48 f024663d 2021-09-05 stsp 
 49 f024663d 2021-09-05 stsp const struct got_error *
 50 f024663d 2021-09-05 stsp got_pkt_flushpkt(int fd, int chattygot)
 51 f024663d 2021-09-05 stsp {
 52 f024663d 2021-09-05 stsp 	ssize_t w;
 53 f024663d 2021-09-05 stsp 
 54 f024663d 2021-09-05 stsp 	if (chattygot > 1)
 55 f024663d 2021-09-05 stsp 		fprintf(stderr, "%s: writepkt: 0000\n", getprogname());
 56 f024663d 2021-09-05 stsp 
 57 f024663d 2021-09-05 stsp 	w = write(fd, "0000", 4);
 58 f024663d 2021-09-05 stsp 	if (w == -1)
 59 f024663d 2021-09-05 stsp 		return got_error_from_errno("write");
 60 f024663d 2021-09-05 stsp 	if (w != 4)
 61 f024663d 2021-09-05 stsp 		return got_error(GOT_ERR_IO);
 62 f024663d 2021-09-05 stsp 	return NULL;
 63 f024663d 2021-09-05 stsp }
 64 f024663d 2021-09-05 stsp 
 65 b77bad15 2024-04-19 me const struct got_error *
 66 b77bad15 2024-04-19 me got_pkt_readlen(int *len, const char *str, int chattygot)
 67 b77bad15 2024-04-19 me {
 68 b77bad15 2024-04-19 me 	int	 i;
 69 b77bad15 2024-04-19 me 
 70 b77bad15 2024-04-19 me 	*len = 0;
 71 b77bad15 2024-04-19 me 	for (i = 0; i < 4; i++) {
 72 b77bad15 2024-04-19 me 		if ('0' <= str[i] && str[i] <= '9') {
 73 b77bad15 2024-04-19 me 			*len *= 16;
 74 b77bad15 2024-04-19 me 			*len += str[i] - '0';
 75 b77bad15 2024-04-19 me 		} else if ('a' <= str[i] && str[i] <= 'f') {
 76 b77bad15 2024-04-19 me 			*len *= 16;
 77 b77bad15 2024-04-19 me 			*len += str[i] - 'a' + 10;
 78 b77bad15 2024-04-19 me 		} else {
 79 b77bad15 2024-04-19 me 			if (chattygot)
 80 b77bad15 2024-04-19 me 				fprintf(stderr, "%s: bad length: '.4%s'\n",
 81 b77bad15 2024-04-19 me 				    getprogname(), str);
 82 b77bad15 2024-04-19 me 			return got_error_msg(GOT_ERR_BAD_PACKET,
 83 b77bad15 2024-04-19 me 			    "packet length has invalid format");
 84 b77bad15 2024-04-19 me 		}
 85 b77bad15 2024-04-19 me 	}
 86 b77bad15 2024-04-19 me 	return NULL;
 87 b77bad15 2024-04-19 me }
 88 b77bad15 2024-04-19 me 
 89 f024663d 2021-09-05 stsp /*
 90 f024663d 2021-09-05 stsp  * Packet header contains a 4-byte hexstring which specifies the length
 91 f024663d 2021-09-05 stsp  * of data which follows.
 92 f024663d 2021-09-05 stsp  */
 93 f024663d 2021-09-05 stsp const struct got_error *
 94 f024663d 2021-09-05 stsp got_pkt_readhdr(int *datalen, int fd, int chattygot)
 95 f024663d 2021-09-05 stsp {
 96 b77bad15 2024-04-19 me 	static const struct got_error *err;
 97 b77bad15 2024-04-19 me 	char lenstr[4];
 98 f024663d 2021-09-05 stsp 	ssize_t r;
 99 b77bad15 2024-04-19 me 	int n;
100 f024663d 2021-09-05 stsp 
101 f024663d 2021-09-05 stsp 	*datalen = 0;
102 f024663d 2021-09-05 stsp 
103 f024663d 2021-09-05 stsp 	err = got_pkt_readn(&r, fd, lenstr, 4);
104 f024663d 2021-09-05 stsp 	if (err)
105 f024663d 2021-09-05 stsp 		return err;
106 f024663d 2021-09-05 stsp 	if (r == 0) {
107 f024663d 2021-09-05 stsp 		/* implicit "0000" */
108 f024663d 2021-09-05 stsp 		if (chattygot > 1)
109 f024663d 2021-09-05 stsp 			fprintf(stderr, "%s: readpkt: 0000\n", getprogname());
110 f024663d 2021-09-05 stsp 		return NULL;
111 f024663d 2021-09-05 stsp 	}
112 f024663d 2021-09-05 stsp 	if (r != 4)
113 f024663d 2021-09-05 stsp 		return got_error_msg(GOT_ERR_BAD_PACKET,
114 f024663d 2021-09-05 stsp 		    "wrong packet header length");
115 f024663d 2021-09-05 stsp 
116 b77bad15 2024-04-19 me 	err = got_pkt_readlen(&n, lenstr, chattygot);
117 f024663d 2021-09-05 stsp 	if (n == 0)
118 b77bad15 2024-04-19 me 		return err;
119 f024663d 2021-09-05 stsp 	if (n <= 4)
120 f024663d 2021-09-05 stsp 		return got_error_msg(GOT_ERR_BAD_PACKET, "packet too short");
121 b77bad15 2024-04-19 me 	n -= 4;
122 f024663d 2021-09-05 stsp 
123 f024663d 2021-09-05 stsp 	*datalen = n;
124 f024663d 2021-09-05 stsp 	return NULL;
125 f024663d 2021-09-05 stsp }
126 f024663d 2021-09-05 stsp 
127 f024663d 2021-09-05 stsp const struct got_error *
128 f024663d 2021-09-05 stsp got_pkt_readpkt(int *outlen, int fd, char *buf, int buflen, int chattygot)
129 f024663d 2021-09-05 stsp {
130 f024663d 2021-09-05 stsp 	const struct got_error *err = NULL;
131 f024663d 2021-09-05 stsp 	int datalen, i;
132 f024663d 2021-09-05 stsp 	ssize_t n;
133 f024663d 2021-09-05 stsp 
134 f024663d 2021-09-05 stsp 	err = got_pkt_readhdr(&datalen, fd, chattygot);
135 f024663d 2021-09-05 stsp 	if (err)
136 f024663d 2021-09-05 stsp 		return err;
137 f024663d 2021-09-05 stsp 
138 f024663d 2021-09-05 stsp 	if (datalen > buflen)
139 f024663d 2021-09-05 stsp 		return got_error(GOT_ERR_NO_SPACE);
140 f024663d 2021-09-05 stsp 
141 f024663d 2021-09-05 stsp 	err = got_pkt_readn(&n, fd, buf, datalen);
142 f024663d 2021-09-05 stsp 	if (err)
143 f024663d 2021-09-05 stsp 		return err;
144 f024663d 2021-09-05 stsp 	if (n != datalen)
145 f024663d 2021-09-05 stsp 		return got_error_msg(GOT_ERR_BAD_PACKET, "short packet");
146 f024663d 2021-09-05 stsp 
147 f024663d 2021-09-05 stsp 	if (chattygot > 1) {
148 f024663d 2021-09-05 stsp 		fprintf(stderr, "%s: readpkt: %zd:\t", getprogname(), n);
149 f024663d 2021-09-05 stsp 		for (i = 0; i < n; i++) {
150 99fd9ff4 2022-11-17 op 			if (isprint((unsigned char)buf[i]))
151 f024663d 2021-09-05 stsp 				fputc(buf[i], stderr);
152 f024663d 2021-09-05 stsp 			else
153 f024663d 2021-09-05 stsp 				fprintf(stderr, "[0x%.2x]", buf[i]);
154 f024663d 2021-09-05 stsp 		}
155 f024663d 2021-09-05 stsp 		fputc('\n', stderr);
156 f024663d 2021-09-05 stsp 	}
157 f024663d 2021-09-05 stsp 
158 f024663d 2021-09-05 stsp 	*outlen = n;
159 f024663d 2021-09-05 stsp 	return NULL;
160 f024663d 2021-09-05 stsp }
161 f024663d 2021-09-05 stsp 
162 f024663d 2021-09-05 stsp const struct got_error *
163 f024663d 2021-09-05 stsp got_pkt_writepkt(int fd, char *buf, int nbuf, int chattygot)
164 f024663d 2021-09-05 stsp {
165 f024663d 2021-09-05 stsp 	char len[5];
166 438d0cc3 2022-08-16 op 	int i, ret;
167 f024663d 2021-09-05 stsp 	ssize_t w;
168 f024663d 2021-09-05 stsp 
169 438d0cc3 2022-08-16 op 	ret = snprintf(len, sizeof(len), "%04x", nbuf + 4);
170 438d0cc3 2022-08-16 op 	if (ret < 0 || (size_t)ret >= sizeof(len))
171 f024663d 2021-09-05 stsp 		return got_error(GOT_ERR_NO_SPACE);
172 f024663d 2021-09-05 stsp 	w = write(fd, len, 4);
173 f024663d 2021-09-05 stsp 	if (w == -1)
174 f024663d 2021-09-05 stsp 		return got_error_from_errno("write");
175 f024663d 2021-09-05 stsp 	if (w != 4)
176 f024663d 2021-09-05 stsp 		return got_error(GOT_ERR_IO);
177 f024663d 2021-09-05 stsp 	w = write(fd, buf, nbuf);
178 f024663d 2021-09-05 stsp 	if (w == -1)
179 f024663d 2021-09-05 stsp 		return got_error_from_errno("write");
180 f024663d 2021-09-05 stsp 	if (w != nbuf)
181 f024663d 2021-09-05 stsp 		return got_error(GOT_ERR_IO);
182 f024663d 2021-09-05 stsp 	if (chattygot > 1) {
183 f024663d 2021-09-05 stsp 		fprintf(stderr, "%s: writepkt: %s:\t", getprogname(), len);
184 f024663d 2021-09-05 stsp 		for (i = 0; i < nbuf; i++) {
185 99fd9ff4 2022-11-17 op 			if (isprint((unsigned char)buf[i]))
186 f024663d 2021-09-05 stsp 				fputc(buf[i], stderr);
187 f024663d 2021-09-05 stsp 			else
188 f024663d 2021-09-05 stsp 				fprintf(stderr, "[0x%.2x]", buf[i]);
189 f024663d 2021-09-05 stsp 		}
190 f024663d 2021-09-05 stsp 		fputc('\n', stderr);
191 f024663d 2021-09-05 stsp 	}
192 f024663d 2021-09-05 stsp 	return NULL;
193 f024663d 2021-09-05 stsp }