=================================================================== RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/ssh/Attic/bufaux.c,v retrieving revision 1.19 retrieving revision 1.55 diff -u -r1.19 -r1.55 --- src/usr.bin/ssh/Attic/bufaux.c 2001/12/19 07:18:56 1.19 +++ src/usr.bin/ssh/Attic/bufaux.c 2014/01/31 16:39:19 1.55 @@ -1,3 +1,4 @@ +/* $OpenBSD: bufaux.c,v 1.55 2014/01/31 16:39:19 tedu Exp $ */ /* * Author: Tatu Ylonen * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland @@ -36,138 +37,109 @@ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ -#include "includes.h" -RCSID("$OpenBSD: bufaux.c,v 1.19 2001/12/19 07:18:56 deraadt Exp $"); +#include #include -#include "bufaux.h" + +#include +#include +#include + #include "xmalloc.h" -#include "getput.h" +#include "buffer.h" #include "log.h" +#include "misc.h" /* - * Stores an BIGNUM in the buffer with a 2-byte msb first bit count, followed - * by (bits+7)/8 bytes of binary data, msb first. + * Returns integers from the buffer (msb first). */ -void -buffer_put_bignum(Buffer *buffer, BIGNUM *value) + +int +buffer_get_short_ret(u_short *ret, Buffer *buffer) { - int bits = BN_num_bits(value); - int bin_size = (bits + 7) / 8; - u_char *buf = xmalloc(bin_size); - int oi; - char msg[2]; + u_char buf[2]; - /* Get the value of in binary */ - oi = BN_bn2bin(value, buf); - if (oi != bin_size) - fatal("buffer_put_bignum: BN_bn2bin() failed: oi %d != bin_size %d", - oi, bin_size); + if (buffer_get_ret(buffer, (char *) buf, 2) == -1) + return (-1); + *ret = get_u16(buf); + return (0); +} - /* Store the number of bits in the buffer in two bytes, msb first. */ - PUT_16BIT(msg, bits); - buffer_append(buffer, msg, 2); - /* Store the binary data. */ - buffer_append(buffer, (char *)buf, oi); +u_short +buffer_get_short(Buffer *buffer) +{ + u_short ret; - memset(buf, 0, bin_size); - xfree(buf); + if (buffer_get_short_ret(&ret, buffer) == -1) + fatal("buffer_get_short: buffer error"); + + return (ret); } -/* - * Retrieves an BIGNUM from the buffer. - */ int -buffer_get_bignum(Buffer *buffer, BIGNUM *value) +buffer_get_int_ret(u_int *ret, Buffer *buffer) { - int bits, bytes; - u_char buf[2], *bin; + u_char buf[4]; - /* Get the number for bits. */ - buffer_get(buffer, (char *) buf, 2); - bits = GET_16BIT(buf); - /* Compute the number of binary bytes that follow. */ - bytes = (bits + 7) / 8; - if (buffer_len(buffer) < bytes) - fatal("buffer_get_bignum: input buffer too small"); - bin = (u_char *) buffer_ptr(buffer); - BN_bin2bn(bin, bytes, value); - buffer_consume(buffer, bytes); - - return 2 + bytes; + if (buffer_get_ret(buffer, (char *) buf, 4) == -1) + return (-1); + if (ret != NULL) + *ret = get_u32(buf); + return (0); } -/* - * Stores an BIGNUM in the buffer in SSH2 format. - */ -void -buffer_put_bignum2(Buffer *buffer, BIGNUM *value) +u_int +buffer_get_int(Buffer *buffer) { - int bytes = BN_num_bytes(value) + 1; - u_char *buf = xmalloc(bytes); - int oi; - int hasnohigh = 0; - buf[0] = '\0'; - /* Get the value of in binary */ - oi = BN_bn2bin(value, buf+1); - if (oi != bytes-1) - fatal("buffer_put_bignum: BN_bn2bin() failed: oi %d != bin_size %d", - oi, bytes); - hasnohigh = (buf[1] & 0x80) ? 0 : 1; - if (value->neg) { - /**XXX should be two's-complement */ - int i, carry; - u_char *uc = buf; - log("negativ!"); - for (i = bytes-1, carry = 1; i>=0; i--) { - uc[i] ^= 0xff; - if (carry) - carry = !++uc[i]; - } - } - buffer_put_string(buffer, buf+hasnohigh, bytes-hasnohigh); - memset(buf, 0, bytes); - xfree(buf); + u_int ret; + + if (buffer_get_int_ret(&ret, buffer) == -1) + fatal("buffer_get_int: buffer error"); + + return (ret); } int -buffer_get_bignum2(Buffer *buffer, BIGNUM *value) +buffer_get_int64_ret(u_int64_t *ret, Buffer *buffer) { - /**XXX should be two's-complement */ - int len; - u_char *bin = (u_char *)buffer_get_string(buffer, (u_int *)&len); - BN_bin2bn(bin, len, value); - xfree(bin); - return len; -} + u_char buf[8]; -/* - * Returns an integer from the buffer (4 bytes, msb first). - */ -u_int -buffer_get_int(Buffer *buffer) -{ - u_char buf[4]; - buffer_get(buffer, (char *) buf, 4); - return GET_32BIT(buf); + if (buffer_get_ret(buffer, (char *) buf, 8) == -1) + return (-1); + if (ret != NULL) + *ret = get_u64(buf); + return (0); } u_int64_t buffer_get_int64(Buffer *buffer) { - u_char buf[8]; - buffer_get(buffer, (char *) buf, 8); - return GET_64BIT(buf); + u_int64_t ret; + + if (buffer_get_int64_ret(&ret, buffer) == -1) + fatal("buffer_get_int: buffer error"); + + return (ret); } /* - * Stores an integer in the buffer in 4 bytes, msb first. + * Stores integers in the buffer, msb first. */ void +buffer_put_short(Buffer *buffer, u_short value) +{ + char buf[2]; + + put_u16(buf, value); + buffer_append(buffer, buf, 2); +} + +void buffer_put_int(Buffer *buffer, u_int value) { char buf[4]; - PUT_32BIT(buf, value); + + put_u32(buf, value); buffer_append(buffer, buf, 4); } @@ -175,7 +147,8 @@ buffer_put_int64(Buffer *buffer, u_int64_t value) { char buf[8]; - PUT_64BIT(buf, value); + + put_u64(buf, value); buffer_append(buffer, buf, 8); } @@ -187,27 +160,109 @@ * will be stored there. A null character will be automatically appended * to the returned string, and is not counted in length. */ -char * -buffer_get_string(Buffer *buffer, u_int *length_ptr) +void * +buffer_get_string_ret(Buffer *buffer, u_int *length_ptr) { + u_char *value; u_int len; - char *value; + /* Get the length. */ - len = buffer_get_int(buffer); - if (len > 256 * 1024) - fatal("Received packet with bad string length %d", len); + if (buffer_get_int_ret(&len, buffer) != 0) { + error("buffer_get_string_ret: cannot extract length"); + return (NULL); + } + if (len > 256 * 1024) { + error("buffer_get_string_ret: bad string length %u", len); + return (NULL); + } /* Allocate space for the string. Add one byte for a null character. */ value = xmalloc(len + 1); /* Get the string. */ - buffer_get(buffer, value, len); + if (buffer_get_ret(buffer, value, len) == -1) { + error("buffer_get_string_ret: buffer_get failed"); + free(value); + return (NULL); + } /* Append a null character to make processing easier. */ - value[len] = 0; + value[len] = '\0'; /* Optionally return the length of the string. */ if (length_ptr) *length_ptr = len; - return value; + return (value); } +void * +buffer_get_string(Buffer *buffer, u_int *length_ptr) +{ + void *ret; + + if ((ret = buffer_get_string_ret(buffer, length_ptr)) == NULL) + fatal("buffer_get_string: buffer error"); + return (ret); +} + +char * +buffer_get_cstring_ret(Buffer *buffer, u_int *length_ptr) +{ + u_int length; + char *cp, *ret = buffer_get_string_ret(buffer, &length); + + if (ret == NULL) + return NULL; + if ((cp = memchr(ret, '\0', length)) != NULL) { + /* XXX allow \0 at end-of-string for a while, remove later */ + if (cp == ret + length - 1) + error("buffer_get_cstring_ret: string contains \\0"); + else { + explicit_bzero(ret, length); + free(ret); + return NULL; + } + } + if (length_ptr != NULL) + *length_ptr = length; + return ret; +} + +char * +buffer_get_cstring(Buffer *buffer, u_int *length_ptr) +{ + char *ret; + + if ((ret = buffer_get_cstring_ret(buffer, length_ptr)) == NULL) + fatal("buffer_get_cstring: buffer error"); + return ret; +} + +void * +buffer_get_string_ptr_ret(Buffer *buffer, u_int *length_ptr) +{ + void *ptr; + u_int len; + + if (buffer_get_int_ret(&len, buffer) != 0) + return NULL; + if (len > 256 * 1024) { + error("buffer_get_string_ptr: bad string length %u", len); + return NULL; + } + ptr = buffer_ptr(buffer); + buffer_consume(buffer, len); + if (length_ptr) + *length_ptr = len; + return (ptr); +} + +void * +buffer_get_string_ptr(Buffer *buffer, u_int *length_ptr) +{ + void *ret; + + if ((ret = buffer_get_string_ptr_ret(buffer, length_ptr)) == NULL) + fatal("buffer_get_string_ptr: buffer error"); + return (ret); +} + /* * Stores and arbitrary binary string in the buffer. */ @@ -220,6 +275,8 @@ void buffer_put_cstring(Buffer *buffer, const char *s) { + if (s == NULL) + fatal("buffer_put_cstring: s == NULL"); buffer_put_string(buffer, s, strlen(s)); } @@ -227,11 +284,23 @@ * Returns a character from the buffer (0 - 255). */ int +buffer_get_char_ret(u_char *ret, Buffer *buffer) +{ + if (buffer_get_ret(buffer, ret, 1) == -1) { + error("buffer_get_char_ret: buffer_get_ret failed"); + return (-1); + } + return (0); +} + +int buffer_get_char(Buffer *buffer) { - char ch; - buffer_get(buffer, &ch, 1); - return (u_char) ch; + u_char ch; + + if (buffer_get_char_ret(&ch, buffer) == -1) + fatal("buffer_get_char: buffer error"); + return ch; } /* @@ -241,5 +310,79 @@ buffer_put_char(Buffer *buffer, int value) { char ch = value; + buffer_append(buffer, &ch, 1); } + +/* Pseudo bignum functions */ + +void * +buffer_get_bignum2_as_string_ret(Buffer *buffer, u_int *length_ptr) +{ + u_int len; + u_char *bin, *p, *ret; + + if ((p = bin = buffer_get_string_ret(buffer, &len)) == NULL) { + error("%s: invalid bignum", __func__); + return NULL; + } + + if (len > 0 && (bin[0] & 0x80)) { + error("%s: negative numbers not supported", __func__); + free(bin); + return NULL; + } + if (len > 8 * 1024) { + error("%s: cannot handle BN of size %d", __func__, len); + free(bin); + return NULL; + } + /* Skip zero prefix on numbers with the MSB set */ + if (len > 1 && bin[0] == 0x00 && (bin[1] & 0x80) != 0) { + p++; + len--; + } + ret = xmalloc(len); + memcpy(ret, p, len); + memset(p, '\0', len); + free(bin); + return ret; +} + +void * +buffer_get_bignum2_as_string(Buffer *buffer, u_int *l) +{ + void *ret = buffer_get_bignum2_as_string_ret(buffer, l); + + if (ret == NULL) + fatal("%s: buffer error", __func__); + return ret; +} + +/* + * Stores a string using the bignum encoding rules (\0 pad if MSB set). + */ +void +buffer_put_bignum2_from_string(Buffer *buffer, const u_char *s, u_int l) +{ + u_char *buf, *p; + int pad = 0; + + if (l > 8 * 1024) + fatal("%s: length %u too long", __func__, l); + p = buf = xmalloc(l + 1); + /* + * If most significant bit is set then prepend a zero byte to + * avoid interpretation as a negative number. + */ + if (l > 0 && (s[0] & 0x80) != 0) { + *p++ = '\0'; + pad = 1; + } + memcpy(p, s, l); + buffer_put_string(buffer, buf, l + pad); + memset(buf, '\0', l + pad); + free(buf); +} + +