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);
49 fatal("buffer_put_bignum: BN_bn2bin() failed: oi %d != bin_size %d",
52 /* Store the number of bits in the buffer in two bytes, msb first. */
54 buffer_append(buffer, msg, 2);
55 /* Store the binary data. */
56 buffer_append(buffer, buf, oi);
57 /* Clear the temporary data. */
58 memset(buf, 0, bin_size);
62 /* Retrieves an BIGNUM from the buffer. */
65 buffer_get_bignum(Buffer *buffer, BIGNUM *value)
68 unsigned char buf[2], *bin;
70 /* Get the number for bits. */
71 buffer_get(buffer, (char *)buf, 2);
72 bits = GET_16BIT(buf);
73 /* Compute the number of binary bytes that follow. */
74 bytes = (bits + 7) / 8;
76 buffer_get(buffer, bin, bytes);
77 BN_bin2bn(bin, bytes, value);
83 /* Returns an integer from the buffer (4 bytes, msb first). */
85 unsigned int buffer_get_int(Buffer *buffer)
88 buffer_get(buffer, (char *)buf, 4);
89 return GET_32BIT(buf);
92 /* Stores an integer in the buffer in 4 bytes, msb first. */
94 void buffer_put_int(Buffer *buffer, unsigned int value)
97 PUT_32BIT(buf, value);
98 buffer_append(buffer, buf, 4);
101 /* Returns an arbitrary binary string from the buffer. The string cannot
102 be longer than 256k. The returned value points to memory allocated
103 with xmalloc; it is the responsibility of the calling function to free
104 the data. If length_ptr is non-NULL, the length of the returned data
105 will be stored there. A null character will be automatically appended
106 to the returned string, and is not counted in length. */
108 char *buffer_get_string(Buffer *buffer, unsigned int *length_ptr)
112 /* Get the length. */
113 len = buffer_get_int(buffer);
115 fatal("Received packet with bad string length %d", len);
116 /* Allocate space for the string. Add one byte for a null character. */
117 value = xmalloc(len + 1);
118 /* Get the string. */
119 buffer_get(buffer, value, len);
120 /* Append a null character to make processing easier. */
122 /* Optionally return the length of the string. */
128 /* Stores and arbitrary binary string in the buffer. */
130 void buffer_put_string(Buffer *buffer, const void *buf, unsigned int len)
132 buffer_put_int(buffer, len);
133 buffer_append(buffer, buf, len);
136 /* Returns a character from the buffer (0 - 255). */
138 int buffer_get_char(Buffer *buffer)
141 buffer_get(buffer, &ch, 1);
142 return (unsigned char)ch;
145 /* Stores a character in the buffer. */
147 void buffer_put_char(Buffer *buffer, int value)
150 buffer_append(buffer, &ch, 1);