diff options
| author | SkyperTHC | 2026-03-03 06:28:55 +0000 |
|---|---|---|
| committer | SkyperTHC | 2026-03-03 06:28:55 +0000 |
| commit | 5d3573ef7a109ee70416fe94db098fe6a769a798 (patch) | |
| tree | dc2d5b294c9db8ab2db7433511f94e1c4bb8b698 /other/openssh-reverse/buffer.c | |
| parent | c6c59dc73cc4586357f93ab38ecf459e98675cc5 (diff) | |
packetstorm sync
Diffstat (limited to 'other/openssh-reverse/buffer.c')
| -rw-r--r-- | other/openssh-reverse/buffer.c | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/other/openssh-reverse/buffer.c b/other/openssh-reverse/buffer.c new file mode 100644 index 0000000..468d2a0 --- /dev/null +++ b/other/openssh-reverse/buffer.c | |||
| @@ -0,0 +1,162 @@ | |||
| 1 | /* | ||
| 2 | * | ||
| 3 | * buffer.c | ||
| 4 | * | ||
| 5 | * Author: Tatu Ylonen <ylo@cs.hut.fi> | ||
| 6 | * | ||
| 7 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland | ||
| 8 | * All rights reserved | ||
| 9 | * | ||
| 10 | * Created: Sat Mar 18 04:15:33 1995 ylo | ||
| 11 | * | ||
| 12 | * Functions for manipulating fifo buffers (that can grow if needed). | ||
| 13 | * | ||
| 14 | */ | ||
| 15 | |||
| 16 | #include "includes.h" | ||
| 17 | RCSID("$OpenBSD: buffer.c,v 1.7 2000/06/20 01:39:39 markus Exp $"); | ||
| 18 | |||
| 19 | #include "xmalloc.h" | ||
| 20 | #include "buffer.h" | ||
| 21 | #include "ssh.h" | ||
| 22 | |||
| 23 | /* Initializes the buffer structure. */ | ||
| 24 | |||
| 25 | void | ||
| 26 | buffer_init(Buffer *buffer) | ||
| 27 | { | ||
| 28 | buffer->alloc = 4096; | ||
| 29 | buffer->buf = xmalloc(buffer->alloc); | ||
| 30 | memset(buffer->buf, 0, 4096); | ||
| 31 | buffer->offset = 0; | ||
| 32 | buffer->end = 0; | ||
| 33 | } | ||
| 34 | |||
| 35 | /* Frees any memory used for the buffer. */ | ||
| 36 | |||
| 37 | void | ||
| 38 | buffer_free(Buffer *buffer) | ||
| 39 | { | ||
| 40 | memset(buffer->buf, 0, buffer->alloc); | ||
| 41 | xfree(buffer->buf); | ||
| 42 | } | ||
| 43 | |||
| 44 | /* | ||
| 45 | * Clears any data from the buffer, making it empty. This does not actually | ||
| 46 | * zero the memory. | ||
| 47 | */ | ||
| 48 | |||
| 49 | void | ||
| 50 | buffer_clear(Buffer *buffer) | ||
| 51 | { | ||
| 52 | buffer->offset = 0; | ||
| 53 | buffer->end = 0; | ||
| 54 | } | ||
| 55 | |||
| 56 | /* Appends data to the buffer, expanding it if necessary. */ | ||
| 57 | |||
| 58 | void | ||
| 59 | buffer_append(Buffer *buffer, const char *data, unsigned int len) | ||
| 60 | { | ||
| 61 | char *cp; | ||
| 62 | buffer_append_space(buffer, &cp, len); | ||
| 63 | memcpy(cp, data, len); | ||
| 64 | } | ||
| 65 | |||
| 66 | /* | ||
| 67 | * Appends space to the buffer, expanding the buffer if necessary. This does | ||
| 68 | * not actually copy the data into the buffer, but instead returns a pointer | ||
| 69 | * to the allocated region. | ||
| 70 | */ | ||
| 71 | |||
| 72 | void | ||
| 73 | buffer_append_space(Buffer *buffer, char **datap, unsigned int len) | ||
| 74 | { | ||
| 75 | /* If the buffer is empty, start using it from the beginning. */ | ||
| 76 | if (buffer->offset == buffer->end) { | ||
| 77 | buffer->offset = 0; | ||
| 78 | buffer->end = 0; | ||
| 79 | } | ||
| 80 | restart: | ||
| 81 | /* If there is enough space to store all data, store it now. */ | ||
| 82 | if (buffer->end + len < buffer->alloc) { | ||
| 83 | *datap = buffer->buf + buffer->end; | ||
| 84 | buffer->end += len; | ||
| 85 | return; | ||
| 86 | } | ||
| 87 | /* | ||
| 88 | * If the buffer is quite empty, but all data is at the end, move the | ||
| 89 | * data to the beginning and retry. | ||
| 90 | */ | ||
| 91 | if (buffer->offset > buffer->alloc / 2) { | ||
| 92 | memmove(buffer->buf, buffer->buf + buffer->offset, | ||
| 93 | buffer->end - buffer->offset); | ||
| 94 | buffer->end -= buffer->offset; | ||
| 95 | buffer->offset = 0; | ||
| 96 | goto restart; | ||
| 97 | } | ||
| 98 | /* Increase the size of the buffer and retry. */ | ||
| 99 | buffer->alloc += len + 32768; | ||
| 100 | buffer->buf = xrealloc(buffer->buf, buffer->alloc); | ||
| 101 | goto restart; | ||
| 102 | } | ||
| 103 | |||
| 104 | /* Returns the number of bytes of data in the buffer. */ | ||
| 105 | |||
| 106 | unsigned int | ||
| 107 | buffer_len(Buffer *buffer) | ||
| 108 | { | ||
| 109 | return buffer->end - buffer->offset; | ||
| 110 | } | ||
| 111 | |||
| 112 | /* Gets data from the beginning of the buffer. */ | ||
| 113 | |||
| 114 | void | ||
| 115 | buffer_get(Buffer *buffer, char *buf, unsigned int len) | ||
| 116 | { | ||
| 117 | if (len > buffer->end - buffer->offset) | ||
| 118 | fatal("buffer_get: trying to get more bytes than in buffer"); | ||
| 119 | memcpy(buf, buffer->buf + buffer->offset, len); | ||
| 120 | buffer->offset += len; | ||
| 121 | } | ||
| 122 | |||
| 123 | /* Consumes the given number of bytes from the beginning of the buffer. */ | ||
| 124 | |||
| 125 | void | ||
| 126 | buffer_consume(Buffer *buffer, unsigned int bytes) | ||
| 127 | { | ||
| 128 | if (bytes > buffer->end - buffer->offset) | ||
| 129 | fatal("buffer_consume: trying to get more bytes than in buffer"); | ||
| 130 | buffer->offset += bytes; | ||
| 131 | } | ||
| 132 | |||
| 133 | /* Consumes the given number of bytes from the end of the buffer. */ | ||
| 134 | |||
| 135 | void | ||
| 136 | buffer_consume_end(Buffer *buffer, unsigned int bytes) | ||
| 137 | { | ||
| 138 | if (bytes > buffer->end - buffer->offset) | ||
| 139 | fatal("buffer_consume_end: trying to get more bytes than in buffer"); | ||
| 140 | buffer->end -= bytes; | ||
| 141 | } | ||
| 142 | |||
| 143 | /* Returns a pointer to the first used byte in the buffer. */ | ||
| 144 | |||
| 145 | char * | ||
| 146 | buffer_ptr(Buffer *buffer) | ||
| 147 | { | ||
| 148 | return buffer->buf + buffer->offset; | ||
| 149 | } | ||
| 150 | |||
| 151 | /* Dumps the contents of the buffer to stderr. */ | ||
| 152 | |||
| 153 | void | ||
| 154 | buffer_dump(Buffer *buffer) | ||
| 155 | { | ||
| 156 | int i; | ||
| 157 | unsigned char *ucp = (unsigned char *) buffer->buf; | ||
| 158 | |||
| 159 | for (i = buffer->offset; i < buffer->end; i++) | ||
| 160 | fprintf(stderr, " %02x", ucp[i]); | ||
| 161 | fprintf(stderr, "\n"); | ||
| 162 | } | ||
