5 Author: Tatu Ylonen <ylo@cs.hut.fi>
7 Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
10 Created: Wed Mar 29 02:24:47 1995 ylo
12 Auxiliary functions for storing and retrieving various data types to/from
21 #include <openssl/bn.h>
26 /* Stores an BIGNUM in the buffer with a 2-byte msb first bit count, followed
27 by (bits+7)/8 bytes of binary data, msb first. */
30 buffer_put_bignum(Buffer *buffer, BIGNUM *value)
32 int bits = BN_num_bits(value);
33 int bin_size = (bits + 7) / 8;
34 char *buf = xmalloc(bin_size);
38 /* Get the value of in binary */
39 oi = BN_bn2bin(value, buf);
40 assert(oi == bin_size);
42 /* Store the number of bits in the buffer in two bytes, msb first. */
44 buffer_append(buffer, msg, 2);
45 /* Store the binary data. */
46 buffer_append(buffer, buf, oi);
47 /* Clear the temporary data. */
48 memset(buf, 0, bin_size);
52 /* Retrieves an BIGNUM from the buffer. */
55 buffer_get_bignum(Buffer *buffer, BIGNUM *value)
58 unsigned char buf[2], *bin;
60 /* Get the number for bits. */
61 buffer_get(buffer, (char *)buf, 2);
62 bits = GET_16BIT(buf);
63 /* Compute the number of binary bytes that follow. */
64 bytes = (bits + 7) / 8;
66 buffer_get(buffer, bin, bytes);
67 BN_bin2bn(bin, bytes, value);
73 /* Returns an integer from the buffer (4 bytes, msb first). */
75 unsigned int buffer_get_int(Buffer *buffer)
78 buffer_get(buffer, (char *)buf, 4);
79 return GET_32BIT(buf);
82 /* Stores an integer in the buffer in 4 bytes, msb first. */
84 void buffer_put_int(Buffer *buffer, unsigned int value)
87 PUT_32BIT(buf, value);
88 buffer_append(buffer, buf, 4);
91 /* Returns an arbitrary binary string from the buffer. The string cannot
92 be longer than 256k. The returned value points to memory allocated
93 with xmalloc; it is the responsibility of the calling function to free
94 the data. If length_ptr is non-NULL, the length of the returned data
95 will be stored there. A null character will be automatically appended
96 to the returned string, and is not counted in length. */
98 char *buffer_get_string(Buffer *buffer, unsigned int *length_ptr)
102 /* Get the length. */
103 len = buffer_get_int(buffer);
105 fatal("Received packet with bad string length %d", len);
106 /* Allocate space for the string. Add one byte for a null character. */
107 value = xmalloc(len + 1);
108 /* Get the string. */
109 buffer_get(buffer, value, len);
110 /* Append a null character to make processing easier. */
112 /* Optionally return the length of the string. */
118 /* Stores and arbitrary binary string in the buffer. */
120 void buffer_put_string(Buffer *buffer, const void *buf, unsigned int len)
122 buffer_put_int(buffer, len);
123 buffer_append(buffer, buf, len);
126 /* Returns a character from the buffer (0 - 255). */
128 int buffer_get_char(Buffer *buffer)
131 buffer_get(buffer, &ch, 1);
132 return (unsigned char)ch;
135 /* Stores a character in the buffer. */
137 void buffer_put_char(Buffer *buffer, int value)
140 buffer_append(buffer, &ch, 1);