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- /* $OpenBSD: sshbuf-misc.c,v 1.18 2022/01/22 00:43:43 djm Exp $ */
- /*
- * Copyright (c) 2011 Damien Miller
- *
- * Permission to use, copy, modify, and distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
- */
-
- #include "includes.h"
-
- #include <sys/types.h>
- #include <sys/socket.h>
- #include <netinet/in.h>
- #include <errno.h>
- #include <stdlib.h>
- #ifdef HAVE_STDINT_H
- # include <stdint.h>
- #endif
- #include <stdio.h>
- #include <limits.h>
- #include <string.h>
- #include <resolv.h>
- #include <ctype.h>
- #include <unistd.h>
-
- #include "ssherr.h"
- #define SSHBUF_INTERNAL
- #include "sshbuf.h"
-
- void
- sshbuf_dump_data(const void *s, size_t len, FILE *f)
- {
- size_t i, j;
- const u_char *p = (const u_char *)s;
-
- for (i = 0; i < len; i += 16) {
- fprintf(f, "%.4zu: ", i);
- for (j = i; j < i + 16; j++) {
- if (j < len)
- fprintf(f, "%02x ", p[j]);
- else
- fprintf(f, " ");
- }
- fprintf(f, " ");
- for (j = i; j < i + 16; j++) {
- if (j < len) {
- if (isascii(p[j]) && isprint(p[j]))
- fprintf(f, "%c", p[j]);
- else
- fprintf(f, ".");
- }
- }
- fprintf(f, "\n");
- }
- }
-
- void
- sshbuf_dump(const struct sshbuf *buf, FILE *f)
- {
- fprintf(f, "buffer len = %zu\n", sshbuf_len(buf));
- sshbuf_dump_data(sshbuf_ptr(buf), sshbuf_len(buf), f);
- }
-
- char *
- sshbuf_dtob16(struct sshbuf *buf)
- {
- size_t i, j, len = sshbuf_len(buf);
- const u_char *p = sshbuf_ptr(buf);
- char *ret;
- const char hex[] = "0123456789abcdef";
-
- if (len == 0)
- return strdup("");
- if (SIZE_MAX / 2 <= len || (ret = malloc(len * 2 + 1)) == NULL)
- return NULL;
- for (i = j = 0; i < len; i++) {
- ret[j++] = hex[(p[i] >> 4) & 0xf];
- ret[j++] = hex[p[i] & 0xf];
- }
- ret[j] = '\0';
- return ret;
- }
-
- int
- sshbuf_dtob64(const struct sshbuf *d, struct sshbuf *b64, int wrap)
- {
- size_t i, slen = 0;
- char *s = NULL;
- int r;
-
- if (d == NULL || b64 == NULL || sshbuf_len(d) >= SIZE_MAX / 2)
- return SSH_ERR_INVALID_ARGUMENT;
- if (sshbuf_len(d) == 0)
- return 0;
- slen = ((sshbuf_len(d) + 2) / 3) * 4 + 1;
- if ((s = malloc(slen)) == NULL)
- return SSH_ERR_ALLOC_FAIL;
- if (b64_ntop(sshbuf_ptr(d), sshbuf_len(d), s, slen) == -1) {
- r = SSH_ERR_INTERNAL_ERROR;
- goto fail;
- }
- if (wrap) {
- for (i = 0; s[i] != '\0'; i++) {
- if ((r = sshbuf_put_u8(b64, s[i])) != 0)
- goto fail;
- if (i % 70 == 69 && (r = sshbuf_put_u8(b64, '\n')) != 0)
- goto fail;
- }
- if ((i - 1) % 70 != 69 && (r = sshbuf_put_u8(b64, '\n')) != 0)
- goto fail;
- } else {
- if ((r = sshbuf_put(b64, s, strlen(s))) != 0)
- goto fail;
- }
- /* Success */
- r = 0;
- fail:
- freezero(s, slen);
- return r;
- }
-
- char *
- sshbuf_dtob64_string(const struct sshbuf *buf, int wrap)
- {
- struct sshbuf *tmp;
- char *ret;
-
- if ((tmp = sshbuf_new()) == NULL)
- return NULL;
- if (sshbuf_dtob64(buf, tmp, wrap) != 0) {
- sshbuf_free(tmp);
- return NULL;
- }
- ret = sshbuf_dup_string(tmp);
- sshbuf_free(tmp);
- return ret;
- }
-
- int
- sshbuf_b64tod(struct sshbuf *buf, const char *b64)
- {
- size_t plen = strlen(b64);
- int nlen, r;
- u_char *p;
-
- if (plen == 0)
- return 0;
- if ((p = malloc(plen)) == NULL)
- return SSH_ERR_ALLOC_FAIL;
- if ((nlen = b64_pton(b64, p, plen)) < 0) {
- freezero(p, plen);
- return SSH_ERR_INVALID_FORMAT;
- }
- if ((r = sshbuf_put(buf, p, nlen)) < 0) {
- freezero(p, plen);
- return r;
- }
- freezero(p, plen);
- return 0;
- }
-
- int
- sshbuf_dtourlb64(const struct sshbuf *d, struct sshbuf *b64, int wrap)
- {
- int r = SSH_ERR_INTERNAL_ERROR;
- u_char *p;
- struct sshbuf *b = NULL;
- size_t i, l;
-
- if ((b = sshbuf_new()) == NULL)
- return SSH_ERR_ALLOC_FAIL;
- /* Encode using regular base64; we'll transform it once done */
- if ((r = sshbuf_dtob64(d, b, wrap)) != 0)
- goto out;
- /* remove padding from end of encoded string*/
- for (;;) {
- l = sshbuf_len(b);
- if (l <= 1 || sshbuf_ptr(b) == NULL) {
- r = SSH_ERR_INTERNAL_ERROR;
- goto out;
- }
- if (sshbuf_ptr(b)[l - 1] != '=')
- break;
- if ((r = sshbuf_consume_end(b, 1)) != 0)
- goto out;
- }
- /* Replace characters with rfc4648 equivalents */
- l = sshbuf_len(b);
- if ((p = sshbuf_mutable_ptr(b)) == NULL) {
- r = SSH_ERR_INTERNAL_ERROR;
- goto out;
- }
- for (i = 0; i < l; i++) {
- if (p[i] == '+')
- p[i] = '-';
- else if (p[i] == '/')
- p[i] = '_';
- }
- r = sshbuf_putb(b64, b);
- out:
- sshbuf_free(b);
- return r;
- }
-
- char *
- sshbuf_dup_string(struct sshbuf *buf)
- {
- const u_char *p = NULL, *s = sshbuf_ptr(buf);
- size_t l = sshbuf_len(buf);
- char *r;
-
- if (s == NULL || l > SIZE_MAX)
- return NULL;
- /* accept a nul only as the last character in the buffer */
- if (l > 0 && (p = memchr(s, '\0', l)) != NULL) {
- if (p != s + l - 1)
- return NULL;
- l--; /* the nul is put back below */
- }
- if ((r = malloc(l + 1)) == NULL)
- return NULL;
- if (l > 0)
- memcpy(r, s, l);
- r[l] = '\0';
- return r;
- }
-
- int
- sshbuf_cmp(const struct sshbuf *b, size_t offset,
- const void *s, size_t len)
- {
- if (sshbuf_ptr(b) == NULL)
- return SSH_ERR_INTERNAL_ERROR;
- if (offset > SSHBUF_SIZE_MAX || len > SSHBUF_SIZE_MAX || len == 0)
- return SSH_ERR_INVALID_ARGUMENT;
- if (offset + len > sshbuf_len(b))
- return SSH_ERR_MESSAGE_INCOMPLETE;
- if (timingsafe_bcmp(sshbuf_ptr(b) + offset, s, len) != 0)
- return SSH_ERR_INVALID_FORMAT;
- return 0;
- }
-
- int
- sshbuf_find(const struct sshbuf *b, size_t start_offset,
- const void *s, size_t len, size_t *offsetp)
- {
- void *p;
-
- if (offsetp != NULL)
- *offsetp = 0;
- if (sshbuf_ptr(b) == NULL)
- return SSH_ERR_INTERNAL_ERROR;
- if (start_offset > SSHBUF_SIZE_MAX || len > SSHBUF_SIZE_MAX || len == 0)
- return SSH_ERR_INVALID_ARGUMENT;
- if (start_offset > sshbuf_len(b) || start_offset + len > sshbuf_len(b))
- return SSH_ERR_MESSAGE_INCOMPLETE;
- if ((p = memmem(sshbuf_ptr(b) + start_offset,
- sshbuf_len(b) - start_offset, s, len)) == NULL)
- return SSH_ERR_INVALID_FORMAT;
- if (offsetp != NULL)
- *offsetp = (const u_char *)p - sshbuf_ptr(b);
- return 0;
- }
-
- int
- sshbuf_read(int fd, struct sshbuf *buf, size_t maxlen, size_t *rlen)
- {
- int r, oerrno;
- size_t adjust;
- ssize_t rr;
- u_char *d;
-
- if (rlen != NULL)
- *rlen = 0;
- if ((r = sshbuf_reserve(buf, maxlen, &d)) != 0)
- return r;
- rr = read(fd, d, maxlen);
- oerrno = errno;
-
- /* Adjust the buffer to include only what was actually read */
- if ((adjust = maxlen - (rr > 0 ? rr : 0)) != 0) {
- if ((r = sshbuf_consume_end(buf, adjust)) != 0) {
- /* avoid returning uninitialised data to caller */
- memset(d + rr, '\0', adjust);
- return SSH_ERR_INTERNAL_ERROR; /* shouldn't happen */
- }
- }
- if (rr < 0) {
- errno = oerrno;
- return SSH_ERR_SYSTEM_ERROR;
- } else if (rr == 0) {
- errno = EPIPE;
- return SSH_ERR_SYSTEM_ERROR;
- }
- /* success */
- if (rlen != NULL)
- *rlen = (size_t)rr;
- return 0;
- }
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