diff options
author | Damien Miller <djm@mindrot.org> | 1999-10-27 13:42:43 +1000 |
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committer | Damien Miller <djm@mindrot.org> | 1999-10-27 13:42:43 +1000 |
commit | d4a8b7e34dd619a4debf9a206c81db26d1402ea6 (patch) | |
tree | a47d770a2f790f40d18b0982d4e55fa7cfb1fa3b /bufaux.c |
Initial revision
Diffstat (limited to 'bufaux.c')
-rw-r--r-- | bufaux.c | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/bufaux.c b/bufaux.c new file mode 100644 index 00000000..1ae39d67 --- /dev/null +++ b/bufaux.c @@ -0,0 +1,141 @@ +/* + +bufaux.c + +Author: Tatu Ylonen <ylo@cs.hut.fi> + +Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland + All rights reserved + +Created: Wed Mar 29 02:24:47 1995 ylo + +Auxiliary functions for storing and retrieving various data types to/from +Buffers. + +*/ + +#include "includes.h" +RCSID("$Id: bufaux.c,v 1.1 1999/10/27 03:42:43 damien Exp $"); + +#include "ssh.h" +#include <openssl/bn.h> +#include "bufaux.h" +#include "xmalloc.h" +#include "getput.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. */ + +void +buffer_put_bignum(Buffer *buffer, BIGNUM *value) +{ + int bits = BN_num_bits(value); + int bin_size = (bits + 7) / 8; + char *buf = xmalloc(bin_size); + int oi; + char msg[2]; + + /* Get the value of in binary */ + oi = BN_bn2bin(value, buf); + assert(oi == bin_size); + + /* 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, buf, oi); + /* Clear the temporary data. */ + memset(buf, 0, bin_size); + xfree(buf); +} + +/* Retrieves an BIGNUM from the buffer. */ + +int +buffer_get_bignum(Buffer *buffer, BIGNUM *value) +{ + int bits, bytes; + unsigned char buf[2], *bin; + + /* 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; + bin = xmalloc(bytes); + buffer_get(buffer, bin, bytes); + BN_bin2bn(bin, bytes, value); + xfree(bin); + + return 2 + bytes; +} + +/* Returns an integer from the buffer (4 bytes, msb first). */ + +unsigned int buffer_get_int(Buffer *buffer) +{ + unsigned char buf[4]; + buffer_get(buffer, (char *)buf, 4); + return GET_32BIT(buf); +} + +/* Stores an integer in the buffer in 4 bytes, msb first. */ + +void buffer_put_int(Buffer *buffer, unsigned int value) +{ + char buf[4]; + PUT_32BIT(buf, value); + buffer_append(buffer, buf, 4); +} + +/* Returns an arbitrary binary string from the buffer. The string cannot + be longer than 256k. The returned value points to memory allocated + with xmalloc; it is the responsibility of the calling function to free + the data. If length_ptr is non-NULL, the length of the returned data + 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, unsigned int *length_ptr) +{ + unsigned 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); + /* Allocate space for the string. Add one byte for a null character. */ + value = xmalloc(len + 1); + /* Get the string. */ + buffer_get(buffer, value, len); + /* Append a null character to make processing easier. */ + value[len] = 0; + /* Optionally return the length of the string. */ + if (length_ptr) + *length_ptr = len; + return value; +} + +/* Stores and arbitrary binary string in the buffer. */ + +void buffer_put_string(Buffer *buffer, const void *buf, unsigned int len) +{ + buffer_put_int(buffer, len); + buffer_append(buffer, buf, len); +} + +/* Returns a character from the buffer (0 - 255). */ + +int buffer_get_char(Buffer *buffer) +{ + char ch; + buffer_get(buffer, &ch, 1); + return (unsigned char)ch; +} + +/* Stores a character in the buffer. */ + +void buffer_put_char(Buffer *buffer, int value) +{ + char ch = value; + buffer_append(buffer, &ch, 1); +} |