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 f024663d 2021-09-05 stsp const struct got_error *
 30 0fb910a4 2024-05-05 stsp got_pkt_readn(ssize_t *off, int fd, void *buf, size_t n,
 31 0fb910a4 2024-05-05 stsp     int timeout)
 32 f024663d 2021-09-05 stsp {
 33 6fefa431 2024-05-05 stsp 	const struct got_error *err;
 34 6fefa431 2024-05-05 stsp 	size_t len;
 35 f024663d 2021-09-05 stsp 
 36 6fefa431 2024-05-05 stsp 	err = got_poll_read_full_timeout(fd, &len, buf, n, n,
 37 0fb910a4 2024-05-05 stsp 	    timeout);
 38 6fefa431 2024-05-05 stsp 	if (err)
 39 6fefa431 2024-05-05 stsp 		return err;
 40 6fefa431 2024-05-05 stsp 
 41 6fefa431 2024-05-05 stsp 	/* XXX size_t -> ssize_t */
 42 6fefa431 2024-05-05 stsp 	if (len > SSIZE_MAX)
 43 6fefa431 2024-05-05 stsp 		return got_error(GOT_ERR_RANGE);
 44 6fefa431 2024-05-05 stsp 	*off = len;
 45 f024663d 2021-09-05 stsp 	return NULL;
 46 f024663d 2021-09-05 stsp }
 47 f024663d 2021-09-05 stsp 
 48 f024663d 2021-09-05 stsp const struct got_error *
 49 f024663d 2021-09-05 stsp got_pkt_flushpkt(int fd, int chattygot)
 50 f024663d 2021-09-05 stsp {
 51 f024663d 2021-09-05 stsp 	ssize_t w;
 52 f024663d 2021-09-05 stsp 
 53 f024663d 2021-09-05 stsp 	if (chattygot > 1)
 54 f024663d 2021-09-05 stsp 		fprintf(stderr, "%s: writepkt: 0000\n", getprogname());
 55 f024663d 2021-09-05 stsp 
 56 f024663d 2021-09-05 stsp 	w = write(fd, "0000", 4);
 57 f024663d 2021-09-05 stsp 	if (w == -1)
 58 f024663d 2021-09-05 stsp 		return got_error_from_errno("write");
 59 f024663d 2021-09-05 stsp 	if (w != 4)
 60 f024663d 2021-09-05 stsp 		return got_error(GOT_ERR_IO);
 61 f024663d 2021-09-05 stsp 	return NULL;
 62 f024663d 2021-09-05 stsp }
 63 f024663d 2021-09-05 stsp 
 64 b77bad15 2024-04-19 me const struct got_error *
 65 b77bad15 2024-04-19 me got_pkt_readlen(int *len, const char *str, int chattygot)
 66 b77bad15 2024-04-19 me {
 67 b77bad15 2024-04-19 me 	int	 i;
 68 b77bad15 2024-04-19 me 
 69 b77bad15 2024-04-19 me 	*len = 0;
 70 b77bad15 2024-04-19 me 	for (i = 0; i < 4; i++) {
 71 b77bad15 2024-04-19 me 		if ('0' <= str[i] && str[i] <= '9') {
 72 b77bad15 2024-04-19 me 			*len *= 16;
 73 b77bad15 2024-04-19 me 			*len += str[i] - '0';
 74 b77bad15 2024-04-19 me 		} else if ('a' <= str[i] && str[i] <= 'f') {
 75 b77bad15 2024-04-19 me 			*len *= 16;
 76 b77bad15 2024-04-19 me 			*len += str[i] - 'a' + 10;
 77 b77bad15 2024-04-19 me 		} else {
 78 b77bad15 2024-04-19 me 			if (chattygot)
 79 b77bad15 2024-04-19 me 				fprintf(stderr, "%s: bad length: '.4%s'\n",
 80 b77bad15 2024-04-19 me 				    getprogname(), str);
 81 b77bad15 2024-04-19 me 			return got_error_msg(GOT_ERR_BAD_PACKET,
 82 b77bad15 2024-04-19 me 			    "packet length has invalid format");
 83 b77bad15 2024-04-19 me 		}
 84 b77bad15 2024-04-19 me 	}
 85 b77bad15 2024-04-19 me 	return NULL;
 86 b77bad15 2024-04-19 me }
 87 b77bad15 2024-04-19 me 
 88 f024663d 2021-09-05 stsp /*
 89 f024663d 2021-09-05 stsp  * Packet header contains a 4-byte hexstring which specifies the length
 90 f024663d 2021-09-05 stsp  * of data which follows.
 91 f024663d 2021-09-05 stsp  */
 92 f024663d 2021-09-05 stsp const struct got_error *
 93 0fb910a4 2024-05-05 stsp got_pkt_readhdr(int *datalen, int fd, int chattygot, int timeout)
 94 f024663d 2021-09-05 stsp {
 95 b77bad15 2024-04-19 me 	static const struct got_error *err;
 96 b77bad15 2024-04-19 me 	char lenstr[4];
 97 f024663d 2021-09-05 stsp 	ssize_t r;
 98 b77bad15 2024-04-19 me 	int n;
 99 f024663d 2021-09-05 stsp 
100 f024663d 2021-09-05 stsp 	*datalen = 0;
101 f024663d 2021-09-05 stsp 
102 0fb910a4 2024-05-05 stsp 	err = got_pkt_readn(&r, fd, lenstr, 4, timeout);
103 f024663d 2021-09-05 stsp 	if (err)
104 f024663d 2021-09-05 stsp 		return err;
105 f024663d 2021-09-05 stsp 	if (r == 0) {
106 f024663d 2021-09-05 stsp 		/* implicit "0000" */
107 f024663d 2021-09-05 stsp 		if (chattygot > 1)
108 f024663d 2021-09-05 stsp 			fprintf(stderr, "%s: readpkt: 0000\n", getprogname());
109 f024663d 2021-09-05 stsp 		return NULL;
110 f024663d 2021-09-05 stsp 	}
111 f024663d 2021-09-05 stsp 	if (r != 4)
112 f024663d 2021-09-05 stsp 		return got_error_msg(GOT_ERR_BAD_PACKET,
113 f024663d 2021-09-05 stsp 		    "wrong packet header length");
114 f024663d 2021-09-05 stsp 
115 b77bad15 2024-04-19 me 	err = got_pkt_readlen(&n, lenstr, chattygot);
116 f024663d 2021-09-05 stsp 	if (n == 0)
117 b77bad15 2024-04-19 me 		return err;
118 f024663d 2021-09-05 stsp 	if (n <= 4)
119 f024663d 2021-09-05 stsp 		return got_error_msg(GOT_ERR_BAD_PACKET, "packet too short");
120 b77bad15 2024-04-19 me 	n -= 4;
121 f024663d 2021-09-05 stsp 
122 f024663d 2021-09-05 stsp 	*datalen = n;
123 f024663d 2021-09-05 stsp 	return NULL;
124 f024663d 2021-09-05 stsp }
125 f024663d 2021-09-05 stsp 
126 f024663d 2021-09-05 stsp const struct got_error *
127 0fb910a4 2024-05-05 stsp got_pkt_readpkt(int *outlen, int fd, char *buf, int buflen, int chattygot,
128 0fb910a4 2024-05-05 stsp     int timeout)
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 0fb910a4 2024-05-05 stsp 	err = got_pkt_readhdr(&datalen, fd, chattygot, timeout);
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 0fb910a4 2024-05-05 stsp 	err = got_pkt_readn(&n, fd, buf, datalen, timeout);
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 }