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
24 #include <openssl/bn.h>
34 /* Stores an BIGNUM in the buffer with a 2-byte msb first bit count, followed
35 by (bits+7)/8 bytes of binary data, msb first. */
38 buffer_put_bignum(Buffer *buffer, BIGNUM *value)
40 int bits = BN_num_bits(value);
41 int bin_size = (bits + 7) / 8;
42 char *buf = xmalloc(bin_size);
46 /* Get the value of in binary */
47 oi = BN_bn2bin(value, buf);
48 assert(oi == bin_size);
50 /* Store the number of bits in the buffer in two bytes, msb first. */
52 buffer_append(buffer, msg, 2);
53 /* Store the binary data. */
54 buffer_append(buffer, buf, oi);
55 /* Clear the temporary data. */
56 memset(buf, 0, bin_size);
60 /* Retrieves an BIGNUM from the buffer. */
63 buffer_get_bignum(Buffer *buffer, BIGNUM *value)
66 unsigned char buf[2], *bin;
68 /* Get the number for bits. */
69 buffer_get(buffer, (char *)buf, 2);
70 bits = GET_16BIT(buf);
71 /* Compute the number of binary bytes that follow. */
72 bytes = (bits + 7) / 8;
74 buffer_get(buffer, bin, bytes);
75 BN_bin2bn(bin, bytes, value);
81 /* Returns an integer from the buffer (4 bytes, msb first). */
83 unsigned int buffer_get_int(Buffer *buffer)
86 buffer_get(buffer, (char *)buf, 4);
87 return GET_32BIT(buf);
90 /* Stores an integer in the buffer in 4 bytes, msb first. */
92 void buffer_put_int(Buffer *buffer, unsigned int value)
95 PUT_32BIT(buf, value);
96 buffer_append(buffer, buf, 4);
99 /* Returns an arbitrary binary string from the buffer. The string cannot
100 be longer than 256k. The returned value points to memory allocated
101 with xmalloc; it is the responsibility of the calling function to free
102 the data. If length_ptr is non-NULL, the length of the returned data
103 will be stored there. A null character will be automatically appended
104 to the returned string, and is not counted in length. */
106 char *buffer_get_string(Buffer *buffer, unsigned int *length_ptr)
110 /* Get the length. */
111 len = buffer_get_int(buffer);
113 fatal("Received packet with bad string length %d", len);
114 /* Allocate space for the string. Add one byte for a null character. */
115 value = xmalloc(len + 1);
116 /* Get the string. */
117 buffer_get(buffer, value, len);
118 /* Append a null character to make processing easier. */
120 /* Optionally return the length of the string. */
126 /* Stores and arbitrary binary string in the buffer. */
128 void buffer_put_string(Buffer *buffer, const void *buf, unsigned int len)
130 buffer_put_int(buffer, len);
131 buffer_append(buffer, buf, len);
134 /* Returns a character from the buffer (0 - 255). */
136 int buffer_get_char(Buffer *buffer)
139 buffer_get(buffer, &ch, 1);
140 return (unsigned char)ch;
143 /* Stores a character in the buffer. */
145 void buffer_put_char(Buffer *buffer, int value)
148 buffer_append(buffer, &ch, 1);