diff options
Diffstat (limited to 'tools/plink/misc.c')
| -rw-r--r-- | tools/plink/misc.c | 1564 |
1 files changed, 877 insertions, 687 deletions
diff --git a/tools/plink/misc.c b/tools/plink/misc.c index 89a21f74e..d7c32c49d 100644 --- a/tools/plink/misc.c +++ b/tools/plink/misc.c @@ -1,687 +1,877 @@ -/*
- * Platform-independent routines shared between all PuTTY programs.
- */
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdarg.h>
-#include <limits.h>
-#include <ctype.h>
-#include <assert.h>
-#include "putty.h"
-
-/*
- * Parse a string block size specification. This is approximately a
- * subset of the block size specs supported by GNU fileutils:
- * "nk" = n kilobytes
- * "nM" = n megabytes
- * "nG" = n gigabytes
- * All numbers are decimal, and suffixes refer to powers of two.
- * Case-insensitive.
- */
-unsigned long parse_blocksize(const char *bs)
-{
- char *suf;
- unsigned long r = strtoul(bs, &suf, 10);
- if (*suf != '\0') {
- while (*suf && isspace((unsigned char)*suf)) suf++;
- switch (*suf) {
- case 'k': case 'K':
- r *= 1024ul;
- break;
- case 'm': case 'M':
- r *= 1024ul * 1024ul;
- break;
- case 'g': case 'G':
- r *= 1024ul * 1024ul * 1024ul;
- break;
- case '\0':
- default:
- break;
- }
- }
- return r;
-}
-
-/*
- * Parse a ^C style character specification.
- * Returns NULL in `next' if we didn't recognise it as a control character,
- * in which case `c' should be ignored.
- * The precise current parsing is an oddity inherited from the terminal
- * answerback-string parsing code. All sequences start with ^; all except
- * ^<123> are two characters. The ones that are worth keeping are probably:
- * ^? 127
- * ^@A-Z[\]^_ 0-31
- * a-z 1-26
- * <num> specified by number (decimal, 0octal, 0xHEX)
- * ~ ^ escape
- */
-char ctrlparse(char *s, char **next)
-{
- char c = 0;
- if (*s != '^') {
- *next = NULL;
- } else {
- s++;
- if (*s == '\0') {
- *next = NULL;
- } else if (*s == '<') {
- s++;
- c = (char)strtol(s, next, 0);
- if ((*next == s) || (**next != '>')) {
- c = 0;
- *next = NULL;
- } else
- (*next)++;
- } else if (*s >= 'a' && *s <= 'z') {
- c = (*s - ('a' - 1));
- *next = s+1;
- } else if ((*s >= '@' && *s <= '_') || *s == '?' || (*s & 0x80)) {
- c = ('@' ^ *s);
- *next = s+1;
- } else if (*s == '~') {
- c = '^';
- *next = s+1;
- }
- }
- return c;
-}
-
-prompts_t *new_prompts(void *frontend)
-{
- prompts_t *p = snew(prompts_t);
- p->prompts = NULL;
- p->n_prompts = 0;
- p->frontend = frontend;
- p->data = NULL;
- p->to_server = TRUE; /* to be on the safe side */
- p->name = p->instruction = NULL;
- p->name_reqd = p->instr_reqd = FALSE;
- return p;
-}
-void add_prompt(prompts_t *p, char *promptstr, int echo)
-{
- prompt_t *pr = snew(prompt_t);
- pr->prompt = promptstr;
- pr->echo = echo;
- pr->result = NULL;
- pr->resultsize = 0;
- p->n_prompts++;
- p->prompts = sresize(p->prompts, p->n_prompts, prompt_t *);
- p->prompts[p->n_prompts-1] = pr;
-}
-void prompt_ensure_result_size(prompt_t *pr, int newlen)
-{
- if ((int)pr->resultsize < newlen) {
- char *newbuf;
- newlen = newlen * 5 / 4 + 512; /* avoid too many small allocs */
-
- /*
- * We don't use sresize / realloc here, because we will be
- * storing sensitive stuff like passwords in here, and we want
- * to make sure that the data doesn't get copied around in
- * memory without the old copy being destroyed.
- */
- newbuf = snewn(newlen, char);
- memcpy(newbuf, pr->result, pr->resultsize);
- memset(pr->result, '\0', pr->resultsize);
- sfree(pr->result);
- pr->result = newbuf;
- pr->resultsize = newlen;
- }
-}
-void prompt_set_result(prompt_t *pr, const char *newstr)
-{
- prompt_ensure_result_size(pr, strlen(newstr) + 1);
- strcpy(pr->result, newstr);
-}
-void free_prompts(prompts_t *p)
-{
- size_t i;
- for (i=0; i < p->n_prompts; i++) {
- prompt_t *pr = p->prompts[i];
- memset(pr->result, 0, pr->resultsize); /* burn the evidence */
- sfree(pr->result);
- sfree(pr->prompt);
- sfree(pr);
- }
- sfree(p->prompts);
- sfree(p->name);
- sfree(p->instruction);
- sfree(p);
-}
-
-/* ----------------------------------------------------------------------
- * String handling routines.
- */
-
-char *dupstr(const char *s)
-{
- char *p = NULL;
- if (s) {
- int len = strlen(s);
- p = snewn(len + 1, char);
- strcpy(p, s);
- }
- return p;
-}
-
-/* Allocate the concatenation of N strings. Terminate arg list with NULL. */
-char *dupcat(const char *s1, ...)
-{
- int len;
- char *p, *q, *sn;
- va_list ap;
-
- len = strlen(s1);
- va_start(ap, s1);
- while (1) {
- sn = va_arg(ap, char *);
- if (!sn)
- break;
- len += strlen(sn);
- }
- va_end(ap);
-
- p = snewn(len + 1, char);
- strcpy(p, s1);
- q = p + strlen(p);
-
- va_start(ap, s1);
- while (1) {
- sn = va_arg(ap, char *);
- if (!sn)
- break;
- strcpy(q, sn);
- q += strlen(q);
- }
- va_end(ap);
-
- return p;
-}
-
-void burnstr(char *string) /* sfree(str), only clear it first */
-{
- if (string) {
- memset(string, 0, strlen(string));
- sfree(string);
- }
-}
-
-/*
- * Do an sprintf(), but into a custom-allocated buffer.
- *
- * Currently I'm doing this via vsnprintf. This has worked so far,
- * but it's not good, because vsnprintf is not available on all
- * platforms. There's an ifdef to use `_vsnprintf', which seems
- * to be the local name for it on Windows. Other platforms may
- * lack it completely, in which case it'll be time to rewrite
- * this function in a totally different way.
- *
- * The only `properly' portable solution I can think of is to
- * implement my own format string scanner, which figures out an
- * upper bound for the length of each formatting directive,
- * allocates the buffer as it goes along, and calls sprintf() to
- * actually process each directive. If I ever need to actually do
- * this, some caveats:
- *
- * - It's very hard to find a reliable upper bound for
- * floating-point values. %f, in particular, when supplied with
- * a number near to the upper or lower limit of representable
- * numbers, could easily take several hundred characters. It's
- * probably feasible to predict this statically using the
- * constants in <float.h>, or even to predict it dynamically by
- * looking at the exponent of the specific float provided, but
- * it won't be fun.
- *
- * - Don't forget to _check_, after calling sprintf, that it's
- * used at most the amount of space we had available.
- *
- * - Fault any formatting directive we don't fully understand. The
- * aim here is to _guarantee_ that we never overflow the buffer,
- * because this is a security-critical function. If we see a
- * directive we don't know about, we should panic and die rather
- * than run any risk.
- */
-char *dupprintf(const char *fmt, ...)
-{
- char *ret;
- va_list ap;
- va_start(ap, fmt);
- ret = dupvprintf(fmt, ap);
- va_end(ap);
- return ret;
-}
-char *dupvprintf(const char *fmt, va_list ap)
-{
- char *buf;
- int len, size;
-
- buf = snewn(512, char);
- size = 512;
-
- while (1) {
-#ifdef _WINDOWS
-#define vsnprintf _vsnprintf
-#endif
-#ifdef va_copy
- /* Use the `va_copy' macro mandated by C99, if present.
- * XXX some environments may have this as __va_copy() */
- va_list aq;
- va_copy(aq, ap);
- len = vsnprintf(buf, size, fmt, aq);
- va_end(aq);
-#else
- /* Ugh. No va_copy macro, so do something nasty.
- * Technically, you can't reuse a va_list like this: it is left
- * unspecified whether advancing a va_list pointer modifies its
- * value or something it points to, so on some platforms calling
- * vsnprintf twice on the same va_list might fail hideously
- * (indeed, it has been observed to).
- * XXX the autoconf manual suggests that using memcpy() will give
- * "maximum portability". */
- len = vsnprintf(buf, size, fmt, ap);
-#endif
- if (len >= 0 && len < size) {
- /* This is the C99-specified criterion for snprintf to have
- * been completely successful. */
- return buf;
- } else if (len > 0) {
- /* This is the C99 error condition: the returned length is
- * the required buffer size not counting the NUL. */
- size = len + 1;
- } else {
- /* This is the pre-C99 glibc error condition: <0 means the
- * buffer wasn't big enough, so we enlarge it a bit and hope. */
- size += 512;
- }
- buf = sresize(buf, size, char);
- }
-}
-
-/*
- * Read an entire line of text from a file. Return a buffer
- * malloced to be as big as necessary (caller must free).
- */
-char *fgetline(FILE *fp)
-{
- char *ret = snewn(512, char);
- int size = 512, len = 0;
- while (fgets(ret + len, size - len, fp)) {
- len += strlen(ret + len);
- if (ret[len-1] == '\n')
- break; /* got a newline, we're done */
- size = len + 512;
- ret = sresize(ret, size, char);
- }
- if (len == 0) { /* first fgets returned NULL */
- sfree(ret);
- return NULL;
- }
- ret[len] = '\0';
- return ret;
-}
-
-/* ----------------------------------------------------------------------
- * Base64 encoding routine. This is required in public-key writing
- * but also in HTTP proxy handling, so it's centralised here.
- */
-
-void base64_encode_atom(unsigned char *data, int n, char *out)
-{
- static const char base64_chars[] =
- "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
-
- unsigned word;
-
- word = data[0] << 16;
- if (n > 1)
- word |= data[1] << 8;
- if (n > 2)
- word |= data[2];
- out[0] = base64_chars[(word >> 18) & 0x3F];
- out[1] = base64_chars[(word >> 12) & 0x3F];
- if (n > 1)
- out[2] = base64_chars[(word >> 6) & 0x3F];
- else
- out[2] = '=';
- if (n > 2)
- out[3] = base64_chars[word & 0x3F];
- else
- out[3] = '=';
-}
-
-/* ----------------------------------------------------------------------
- * Generic routines to deal with send buffers: a linked list of
- * smallish blocks, with the operations
- *
- * - add an arbitrary amount of data to the end of the list
- * - remove the first N bytes from the list
- * - return a (pointer,length) pair giving some initial data in
- * the list, suitable for passing to a send or write system
- * call
- * - retrieve a larger amount of initial data from the list
- * - return the current size of the buffer chain in bytes
- */
-
-#define BUFFER_GRANULE 512
-
-struct bufchain_granule {
- struct bufchain_granule *next;
- int buflen, bufpos;
- char buf[BUFFER_GRANULE];
-};
-
-void bufchain_init(bufchain *ch)
-{
- ch->head = ch->tail = NULL;
- ch->buffersize = 0;
-}
-
-void bufchain_clear(bufchain *ch)
-{
- struct bufchain_granule *b;
- while (ch->head) {
- b = ch->head;
- ch->head = ch->head->next;
- sfree(b);
- }
- ch->tail = NULL;
- ch->buffersize = 0;
-}
-
-int bufchain_size(bufchain *ch)
-{
- return ch->buffersize;
-}
-
-void bufchain_add(bufchain *ch, const void *data, int len)
-{
- const char *buf = (const char *)data;
-
- if (len == 0) return;
-
- ch->buffersize += len;
-
- if (ch->tail && ch->tail->buflen < BUFFER_GRANULE) {
- int copylen = min(len, BUFFER_GRANULE - ch->tail->buflen);
- memcpy(ch->tail->buf + ch->tail->buflen, buf, copylen);
- buf += copylen;
- len -= copylen;
- ch->tail->buflen += copylen;
- }
- while (len > 0) {
- int grainlen = min(len, BUFFER_GRANULE);
- struct bufchain_granule *newbuf;
- newbuf = snew(struct bufchain_granule);
- newbuf->bufpos = 0;
- newbuf->buflen = grainlen;
- memcpy(newbuf->buf, buf, grainlen);
- buf += grainlen;
- len -= grainlen;
- if (ch->tail)
- ch->tail->next = newbuf;
- else
- ch->head = ch->tail = newbuf;
- newbuf->next = NULL;
- ch->tail = newbuf;
- }
-}
-
-void bufchain_consume(bufchain *ch, int len)
-{
- struct bufchain_granule *tmp;
-
- assert(ch->buffersize >= len);
- while (len > 0) {
- int remlen = len;
- assert(ch->head != NULL);
- if (remlen >= ch->head->buflen - ch->head->bufpos) {
- remlen = ch->head->buflen - ch->head->bufpos;
- tmp = ch->head;
- ch->head = tmp->next;
- sfree(tmp);
- if (!ch->head)
- ch->tail = NULL;
- } else
- ch->head->bufpos += remlen;
- ch->buffersize -= remlen;
- len -= remlen;
- }
-}
-
-void bufchain_prefix(bufchain *ch, void **data, int *len)
-{
- *len = ch->head->buflen - ch->head->bufpos;
- *data = ch->head->buf + ch->head->bufpos;
-}
-
-void bufchain_fetch(bufchain *ch, void *data, int len)
-{
- struct bufchain_granule *tmp;
- char *data_c = (char *)data;
-
- tmp = ch->head;
-
- assert(ch->buffersize >= len);
- while (len > 0) {
- int remlen = len;
-
- assert(tmp != NULL);
- if (remlen >= tmp->buflen - tmp->bufpos)
- remlen = tmp->buflen - tmp->bufpos;
- memcpy(data_c, tmp->buf + tmp->bufpos, remlen);
-
- tmp = tmp->next;
- len -= remlen;
- data_c += remlen;
- }
-}
-
-/* ----------------------------------------------------------------------
- * My own versions of malloc, realloc and free. Because I want
- * malloc and realloc to bomb out and exit the program if they run
- * out of memory, realloc to reliably call malloc if passed a NULL
- * pointer, and free to reliably do nothing if passed a NULL
- * pointer. We can also put trace printouts in, if we need to; and
- * we can also replace the allocator with an ElectricFence-like
- * one.
- */
-
-#ifdef MINEFIELD
-void *minefield_c_malloc(size_t size);
-void minefield_c_free(void *p);
-void *minefield_c_realloc(void *p, size_t size);
-#endif
-
-#ifdef MALLOC_LOG
-static FILE *fp = NULL;
-
-static char *mlog_file = NULL;
-static int mlog_line = 0;
-
-void mlog(char *file, int line)
-{
- mlog_file = file;
- mlog_line = line;
- if (!fp) {
- fp = fopen("putty_mem.log", "w");
- setvbuf(fp, NULL, _IONBF, BUFSIZ);
- }
- if (fp)
- fprintf(fp, "%s:%d: ", file, line);
-}
-#endif
-
-void *safemalloc(size_t n, size_t size)
-{
- void *p;
-
- if (n > INT_MAX / size) {
- p = NULL;
- } else {
- size *= n;
- if (size == 0) size = 1;
-#ifdef MINEFIELD
- p = minefield_c_malloc(size);
-#else
- p = malloc(size);
-#endif
- }
-
- if (!p) {
- char str[200];
-#ifdef MALLOC_LOG
- sprintf(str, "Out of memory! (%s:%d, size=%d)",
- mlog_file, mlog_line, size);
- fprintf(fp, "*** %s\n", str);
- fclose(fp);
-#else
- strcpy(str, "Out of memory!");
-#endif
- modalfatalbox(str);
- }
-#ifdef MALLOC_LOG
- if (fp)
- fprintf(fp, "malloc(%d) returns %p\n", size, p);
-#endif
- return p;
-}
-
-void *saferealloc(void *ptr, size_t n, size_t size)
-{
- void *p;
-
- if (n > INT_MAX / size) {
- p = NULL;
- } else {
- size *= n;
- if (!ptr) {
-#ifdef MINEFIELD
- p = minefield_c_malloc(size);
-#else
- p = malloc(size);
-#endif
- } else {
-#ifdef MINEFIELD
- p = minefield_c_realloc(ptr, size);
-#else
- p = realloc(ptr, size);
-#endif
- }
- }
-
- if (!p) {
- char str[200];
-#ifdef MALLOC_LOG
- sprintf(str, "Out of memory! (%s:%d, size=%d)",
- mlog_file, mlog_line, size);
- fprintf(fp, "*** %s\n", str);
- fclose(fp);
-#else
- strcpy(str, "Out of memory!");
-#endif
- modalfatalbox(str);
- }
-#ifdef MALLOC_LOG
- if (fp)
- fprintf(fp, "realloc(%p,%d) returns %p\n", ptr, size, p);
-#endif
- return p;
-}
-
-void safefree(void *ptr)
-{
- if (ptr) {
-#ifdef MALLOC_LOG
- if (fp)
- fprintf(fp, "free(%p)\n", ptr);
-#endif
-#ifdef MINEFIELD
- minefield_c_free(ptr);
-#else
- free(ptr);
-#endif
- }
-#ifdef MALLOC_LOG
- else if (fp)
- fprintf(fp, "freeing null pointer - no action taken\n");
-#endif
-}
-
-/* ----------------------------------------------------------------------
- * Debugging routines.
- */
-
-#ifdef DEBUG
-extern void dputs(char *); /* defined in per-platform *misc.c */
-
-void debug_printf(char *fmt, ...)
-{
- char *buf;
- va_list ap;
-
- va_start(ap, fmt);
- buf = dupvprintf(fmt, ap);
- dputs(buf);
- sfree(buf);
- va_end(ap);
-}
-
-
-void debug_memdump(void *buf, int len, int L)
-{
- int i;
- unsigned char *p = buf;
- char foo[17];
- if (L) {
- int delta;
- debug_printf("\t%d (0x%x) bytes:\n", len, len);
- delta = 15 & (unsigned long int) p;
- p -= delta;
- len += delta;
- }
- for (; 0 < len; p += 16, len -= 16) {
- dputs(" ");
- if (L)
- debug_printf("%p: ", p);
- strcpy(foo, "................"); /* sixteen dots */
- for (i = 0; i < 16 && i < len; ++i) {
- if (&p[i] < (unsigned char *) buf) {
- dputs(" "); /* 3 spaces */
- foo[i] = ' ';
- } else {
- debug_printf("%c%02.2x",
- &p[i] != (unsigned char *) buf
- && i % 4 ? '.' : ' ', p[i]
- );
- if (p[i] >= ' ' && p[i] <= '~')
- foo[i] = (char) p[i];
- }
- }
- foo[i] = '\0';
- debug_printf("%*s%s\n", (16 - i) * 3 + 2, "", foo);
- }
-}
-
-#endif /* def DEBUG */
-
-/*
- * Determine whether or not a Conf represents a session which can
- * sensibly be launched right now.
- */
-int conf_launchable(Conf *conf)
-{
- if (conf_get_int(conf, CONF_protocol) == PROT_SERIAL)
- return conf_get_str(conf, CONF_serline)[0] != 0;
- else
- return conf_get_str(conf, CONF_host)[0] != 0;
-}
-
-char const *conf_dest(Conf *conf)
-{
- if (conf_get_int(conf, CONF_protocol) == PROT_SERIAL)
- return conf_get_str(conf, CONF_serline);
- else
- return conf_get_str(conf, CONF_host);
-}
+/* + * Platform-independent routines shared between all PuTTY programs. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <stdarg.h> +#include <limits.h> +#include <ctype.h> +#include <assert.h> +#include "putty.h" + +/* + * Parse a string block size specification. This is approximately a + * subset of the block size specs supported by GNU fileutils: + * "nk" = n kilobytes + * "nM" = n megabytes + * "nG" = n gigabytes + * All numbers are decimal, and suffixes refer to powers of two. + * Case-insensitive. + */ +unsigned long parse_blocksize(const char *bs) +{ + char *suf; + unsigned long r = strtoul(bs, &suf, 10); + if (*suf != '\0') { + while (*suf && isspace((unsigned char)*suf)) suf++; + switch (*suf) { + case 'k': case 'K': + r *= 1024ul; + break; + case 'm': case 'M': + r *= 1024ul * 1024ul; + break; + case 'g': case 'G': + r *= 1024ul * 1024ul * 1024ul; + break; + case '\0': + default: + break; + } + } + return r; +} + +/* + * Parse a ^C style character specification. + * Returns NULL in `next' if we didn't recognise it as a control character, + * in which case `c' should be ignored. + * The precise current parsing is an oddity inherited from the terminal + * answerback-string parsing code. All sequences start with ^; all except + * ^<123> are two characters. The ones that are worth keeping are probably: + * ^? 127 + * ^@A-Z[\]^_ 0-31 + * a-z 1-26 + * <num> specified by number (decimal, 0octal, 0xHEX) + * ~ ^ escape + */ +char ctrlparse(char *s, char **next) +{ + char c = 0; + if (*s != '^') { + *next = NULL; + } else { + s++; + if (*s == '\0') { + *next = NULL; + } else if (*s == '<') { + s++; + c = (char)strtol(s, next, 0); + if ((*next == s) || (**next != '>')) { + c = 0; + *next = NULL; + } else + (*next)++; + } else if (*s >= 'a' && *s <= 'z') { + c = (*s - ('a' - 1)); + *next = s+1; + } else if ((*s >= '@' && *s <= '_') || *s == '?' || (*s & 0x80)) { + c = ('@' ^ *s); + *next = s+1; + } else if (*s == '~') { + c = '^'; + *next = s+1; + } + } + return c; +} + +/* + * Find a character in a string, unless it's a colon contained within + * square brackets. Used for untangling strings of the form + * 'host:port', where host can be an IPv6 literal. + * + * We provide several variants of this function, with semantics like + * various standard string.h functions. + */ +static const char *host_strchr_internal(const char *s, const char *set, + int first) +{ + int brackets = 0; + const char *ret = NULL; + + while (1) { + if (!*s) + return ret; + + if (*s == '[') + brackets++; + else if (*s == ']' && brackets > 0) + brackets--; + else if (brackets && *s == ':') + /* never match */ ; + else if (strchr(set, *s)) { + ret = s; + if (first) + return ret; + } + + s++; + } +} +size_t host_strcspn(const char *s, const char *set) +{ + const char *answer = host_strchr_internal(s, set, TRUE); + if (answer) + return answer - s; + else + return strlen(s); +} +char *host_strchr(const char *s, int c) +{ + char set[2]; + set[0] = c; + set[1] = '\0'; + return (char *) host_strchr_internal(s, set, TRUE); +} +char *host_strrchr(const char *s, int c) +{ + char set[2]; + set[0] = c; + set[1] = '\0'; + return (char *) host_strchr_internal(s, set, FALSE); +} + +#ifdef TEST_HOST_STRFOO +int main(void) +{ + int passes = 0, fails = 0; + +#define TEST1(func, string, arg2, suffix, result) do \ + { \ + const char *str = string; \ + unsigned ret = func(string, arg2) suffix; \ + if (ret == result) { \ + passes++; \ + } else { \ + printf("fail: %s(%s,%s)%s = %u, expected %u\n", \ + #func, #string, #arg2, #suffix, ret, result); \ + fails++; \ + } \ +} while (0) + + TEST1(host_strchr, "[1:2:3]:4:5", ':', -str, 7); + TEST1(host_strrchr, "[1:2:3]:4:5", ':', -str, 9); + TEST1(host_strcspn, "[1:2:3]:4:5", "/:",, 7); + TEST1(host_strchr, "[1:2:3]", ':', == NULL, 1); + TEST1(host_strrchr, "[1:2:3]", ':', == NULL, 1); + TEST1(host_strcspn, "[1:2:3]", "/:",, 7); + TEST1(host_strcspn, "[1:2/3]", "/:",, 4); + TEST1(host_strcspn, "[1:2:3]/", "/:",, 7); + + printf("passed %d failed %d total %d\n", passes, fails, passes+fails); + return fails != 0 ? 1 : 0; +} +/* Stubs to stop the rest of this module causing compile failures. */ +void modalfatalbox(char *fmt, ...) {} +int conf_get_int(Conf *conf, int primary) { return 0; } +char *conf_get_str(Conf *conf, int primary) { return NULL; } +#endif /* TEST_HOST_STRFOO */ + +/* + * Trim square brackets off the outside of an IPv6 address literal. + * Leave all other strings unchanged. Returns a fresh dynamically + * allocated string. + */ +char *host_strduptrim(const char *s) +{ + if (s[0] == '[') { + const char *p = s+1; + int colons = 0; + while (*p && *p != ']') { + if (isxdigit((unsigned char)*p)) + /* OK */; + else if (*p == ':') + colons++; + else + break; + p++; + } + if (*p == ']' && !p[1] && colons > 1) { + /* + * This looks like an IPv6 address literal (hex digits and + * at least two colons, contained in square brackets). + * Trim off the brackets. + */ + return dupprintf("%.*s", (int)(p - (s+1)), s+1); + } + } + + /* + * Any other shape of string is simply duplicated. + */ + return dupstr(s); +} + +prompts_t *new_prompts(void *frontend) +{ + prompts_t *p = snew(prompts_t); + p->prompts = NULL; + p->n_prompts = 0; + p->frontend = frontend; + p->data = NULL; + p->to_server = TRUE; /* to be on the safe side */ + p->name = p->instruction = NULL; + p->name_reqd = p->instr_reqd = FALSE; + return p; +} +void add_prompt(prompts_t *p, char *promptstr, int echo) +{ + prompt_t *pr = snew(prompt_t); + pr->prompt = promptstr; + pr->echo = echo; + pr->result = NULL; + pr->resultsize = 0; + p->n_prompts++; + p->prompts = sresize(p->prompts, p->n_prompts, prompt_t *); + p->prompts[p->n_prompts-1] = pr; +} +void prompt_ensure_result_size(prompt_t *pr, int newlen) +{ + if ((int)pr->resultsize < newlen) { + char *newbuf; + newlen = newlen * 5 / 4 + 512; /* avoid too many small allocs */ + + /* + * We don't use sresize / realloc here, because we will be + * storing sensitive stuff like passwords in here, and we want + * to make sure that the data doesn't get copied around in + * memory without the old copy being destroyed. + */ + newbuf = snewn(newlen, char); + memcpy(newbuf, pr->result, pr->resultsize); + smemclr(pr->result, pr->resultsize); + sfree(pr->result); + pr->result = newbuf; + pr->resultsize = newlen; + } +} +void prompt_set_result(prompt_t *pr, const char *newstr) +{ + prompt_ensure_result_size(pr, strlen(newstr) + 1); + strcpy(pr->result, newstr); +} +void free_prompts(prompts_t *p) +{ + size_t i; + for (i=0; i < p->n_prompts; i++) { + prompt_t *pr = p->prompts[i]; + smemclr(pr->result, pr->resultsize); /* burn the evidence */ + sfree(pr->result); + sfree(pr->prompt); + sfree(pr); + } + sfree(p->prompts); + sfree(p->name); + sfree(p->instruction); + sfree(p); +} + +/* ---------------------------------------------------------------------- + * String handling routines. + */ + +char *dupstr(const char *s) +{ + char *p = NULL; + if (s) { + int len = strlen(s); + p = snewn(len + 1, char); + strcpy(p, s); + } + return p; +} + +/* Allocate the concatenation of N strings. Terminate arg list with NULL. */ +char *dupcat(const char *s1, ...) +{ + int len; + char *p, *q, *sn; + va_list ap; + + len = strlen(s1); + va_start(ap, s1); + while (1) { + sn = va_arg(ap, char *); + if (!sn) + break; + len += strlen(sn); + } + va_end(ap); + + p = snewn(len + 1, char); + strcpy(p, s1); + q = p + strlen(p); + + va_start(ap, s1); + while (1) { + sn = va_arg(ap, char *); + if (!sn) + break; + strcpy(q, sn); + q += strlen(q); + } + va_end(ap); + + return p; +} + +void burnstr(char *string) /* sfree(str), only clear it first */ +{ + if (string) { + smemclr(string, strlen(string)); + sfree(string); + } +} + +int toint(unsigned u) +{ + /* + * Convert an unsigned to an int, without running into the + * undefined behaviour which happens by the strict C standard if + * the value overflows. You'd hope that sensible compilers would + * do the sensible thing in response to a cast, but actually I + * don't trust modern compilers not to do silly things like + * assuming that _obviously_ you wouldn't have caused an overflow + * and so they can elide an 'if (i < 0)' test immediately after + * the cast. + * + * Sensible compilers ought of course to optimise this entire + * function into 'just return the input value'! + */ + if (u <= (unsigned)INT_MAX) + return (int)u; + else if (u >= (unsigned)INT_MIN) /* wrap in cast _to_ unsigned is OK */ + return INT_MIN + (int)(u - (unsigned)INT_MIN); + else + return INT_MIN; /* fallback; should never occur on binary machines */ +} + +/* + * Do an sprintf(), but into a custom-allocated buffer. + * + * Currently I'm doing this via vsnprintf. This has worked so far, + * but it's not good, because vsnprintf is not available on all + * platforms. There's an ifdef to use `_vsnprintf', which seems + * to be the local name for it on Windows. Other platforms may + * lack it completely, in which case it'll be time to rewrite + * this function in a totally different way. + * + * The only `properly' portable solution I can think of is to + * implement my own format string scanner, which figures out an + * upper bound for the length of each formatting directive, + * allocates the buffer as it goes along, and calls sprintf() to + * actually process each directive. If I ever need to actually do + * this, some caveats: + * + * - It's very hard to find a reliable upper bound for + * floating-point values. %f, in particular, when supplied with + * a number near to the upper or lower limit of representable + * numbers, could easily take several hundred characters. It's + * probably feasible to predict this statically using the + * constants in <float.h>, or even to predict it dynamically by + * looking at the exponent of the specific float provided, but + * it won't be fun. + * + * - Don't forget to _check_, after calling sprintf, that it's + * used at most the amount of space we had available. + * + * - Fault any formatting directive we don't fully understand. The + * aim here is to _guarantee_ that we never overflow the buffer, + * because this is a security-critical function. If we see a + * directive we don't know about, we should panic and die rather + * than run any risk. + */ +char *dupprintf(const char *fmt, ...) +{ + char *ret; + va_list ap; + va_start(ap, fmt); + ret = dupvprintf(fmt, ap); + va_end(ap); + return ret; +} +char *dupvprintf(const char *fmt, va_list ap) +{ + char *buf; + int len, size; + + buf = snewn(512, char); + size = 512; + + while (1) { +#ifdef _WINDOWS +#define vsnprintf _vsnprintf +#endif +#ifdef va_copy + /* Use the `va_copy' macro mandated by C99, if present. + * XXX some environments may have this as __va_copy() */ + va_list aq; + va_copy(aq, ap); + len = vsnprintf(buf, size, fmt, aq); + va_end(aq); +#else + /* Ugh. No va_copy macro, so do something nasty. + * Technically, you can't reuse a va_list like this: it is left + * unspecified whether advancing a va_list pointer modifies its + * value or something it points to, so on some platforms calling + * vsnprintf twice on the same va_list might fail hideously + * (indeed, it has been observed to). + * XXX the autoconf manual suggests that using memcpy() will give + * "maximum portability". */ + len = vsnprintf(buf, size, fmt, ap); +#endif + if (len >= 0 && len < size) { + /* This is the C99-specified criterion for snprintf to have + * been completely successful. */ + return buf; + } else if (len > 0) { + /* This is the C99 error condition: the returned length is + * the required buffer size not counting the NUL. */ + size = len + 1; + } else { + /* This is the pre-C99 glibc error condition: <0 means the + * buffer wasn't big enough, so we enlarge it a bit and hope. */ + size += 512; + } + buf = sresize(buf, size, char); + } +} + +/* + * Read an entire line of text from a file. Return a buffer + * malloced to be as big as necessary (caller must free). + */ +char *fgetline(FILE *fp) +{ + char *ret = snewn(512, char); + int size = 512, len = 0; + while (fgets(ret + len, size - len, fp)) { + len += strlen(ret + len); + if (ret[len-1] == '\n') + break; /* got a newline, we're done */ + size = len + 512; + ret = sresize(ret, size, char); + } + if (len == 0) { /* first fgets returned NULL */ + sfree(ret); + return NULL; + } + ret[len] = '\0'; + return ret; +} + +/* ---------------------------------------------------------------------- + * Base64 encoding routine. This is required in public-key writing + * but also in HTTP proxy handling, so it's centralised here. + */ + +void base64_encode_atom(unsigned char *data, int n, char *out) +{ + static const char base64_chars[] = + "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; + + unsigned word; + + word = data[0] << 16; + if (n > 1) + word |= data[1] << 8; + if (n > 2) + word |= data[2]; + out[0] = base64_chars[(word >> 18) & 0x3F]; + out[1] = base64_chars[(word >> 12) & 0x3F]; + if (n > 1) + out[2] = base64_chars[(word >> 6) & 0x3F]; + else + out[2] = '='; + if (n > 2) + out[3] = base64_chars[word & 0x3F]; + else + out[3] = '='; +} + +/* ---------------------------------------------------------------------- + * Generic routines to deal with send buffers: a linked list of + * smallish blocks, with the operations + * + * - add an arbitrary amount of data to the end of the list + * - remove the first N bytes from the list + * - return a (pointer,length) pair giving some initial data in + * the list, suitable for passing to a send or write system + * call + * - retrieve a larger amount of initial data from the list + * - return the current size of the buffer chain in bytes + */ + +#define BUFFER_MIN_GRANULE 512 + +struct bufchain_granule { + struct bufchain_granule *next; + char *bufpos, *bufend, *bufmax; +}; + +void bufchain_init(bufchain *ch) +{ + ch->head = ch->tail = NULL; + ch->buffersize = 0; +} + +void bufchain_clear(bufchain *ch) +{ + struct bufchain_granule *b; + while (ch->head) { + b = ch->head; + ch->head = ch->head->next; + sfree(b); + } + ch->tail = NULL; + ch->buffersize = 0; +} + +int bufchain_size(bufchain *ch) +{ + return ch->buffersize; +} + +void bufchain_add(bufchain *ch, const void *data, int len) +{ + const char *buf = (const char *)data; + + if (len == 0) return; + + ch->buffersize += len; + + while (len > 0) { + if (ch->tail && ch->tail->bufend < ch->tail->bufmax) { + int copylen = min(len, ch->tail->bufmax - ch->tail->bufend); + memcpy(ch->tail->bufend, buf, copylen); + buf += copylen; + len -= copylen; + ch->tail->bufend += copylen; + } + if (len > 0) { + int grainlen = + max(sizeof(struct bufchain_granule) + len, BUFFER_MIN_GRANULE); + struct bufchain_granule *newbuf; + newbuf = smalloc(grainlen); + newbuf->bufpos = newbuf->bufend = + (char *)newbuf + sizeof(struct bufchain_granule); + newbuf->bufmax = (char *)newbuf + grainlen; + newbuf->next = NULL; + if (ch->tail) + ch->tail->next = newbuf; + else + ch->head = newbuf; + ch->tail = newbuf; + } + } +} + +void bufchain_consume(bufchain *ch, int len) +{ + struct bufchain_granule *tmp; + + assert(ch->buffersize >= len); + while (len > 0) { + int remlen = len; + assert(ch->head != NULL); + if (remlen >= ch->head->bufend - ch->head->bufpos) { + remlen = ch->head->bufend - ch->head->bufpos; + tmp = ch->head; + ch->head = tmp->next; + if (!ch->head) + ch->tail = NULL; + sfree(tmp); + } else + ch->head->bufpos += remlen; + ch->buffersize -= remlen; + len -= remlen; + } +} + +void bufchain_prefix(bufchain *ch, void **data, int *len) +{ + *len = ch->head->bufend - ch->head->bufpos; + *data = ch->head->bufpos; +} + +void bufchain_fetch(bufchain *ch, void *data, int len) +{ + struct bufchain_granule *tmp; + char *data_c = (char *)data; + + tmp = ch->head; + + assert(ch->buffersize >= len); + while (len > 0) { + int remlen = len; + + assert(tmp != NULL); + if (remlen >= tmp->bufend - tmp->bufpos) + remlen = tmp->bufend - tmp->bufpos; + memcpy(data_c, tmp->bufpos, remlen); + + tmp = tmp->next; + len -= remlen; + data_c += remlen; + } +} + +/* ---------------------------------------------------------------------- + * My own versions of malloc, realloc and free. Because I want + * malloc and realloc to bomb out and exit the program if they run + * out of memory, realloc to reliably call malloc if passed a NULL + * pointer, and free to reliably do nothing if passed a NULL + * pointer. We can also put trace printouts in, if we need to; and + * we can also replace the allocator with an ElectricFence-like + * one. + */ + +#ifdef MINEFIELD +void *minefield_c_malloc(size_t size); +void minefield_c_free(void *p); +void *minefield_c_realloc(void *p, size_t size); +#endif + +#ifdef MALLOC_LOG +static FILE *fp = NULL; + +static char *mlog_file = NULL; +static int mlog_line = 0; + +void mlog(char *file, int line) +{ + mlog_file = file; + mlog_line = line; + if (!fp) { + fp = fopen("putty_mem.log", "w"); + setvbuf(fp, NULL, _IONBF, BUFSIZ); + } + if (fp) + fprintf(fp, "%s:%d: ", file, line); +} +#endif + +void *safemalloc(size_t n, size_t size) +{ + void *p; + + if (n > INT_MAX / size) { + p = NULL; + } else { + size *= n; + if (size == 0) size = 1; +#ifdef MINEFIELD + p = minefield_c_malloc(size); +#else + p = malloc(size); +#endif + } + + if (!p) { + char str[200]; +#ifdef MALLOC_LOG + sprintf(str, "Out of memory! (%s:%d, size=%d)", + mlog_file, mlog_line, size); + fprintf(fp, "*** %s\n", str); + fclose(fp); +#else + strcpy(str, "Out of memory!"); +#endif + modalfatalbox(str); + } +#ifdef MALLOC_LOG + if (fp) + fprintf(fp, "malloc(%d) returns %p\n", size, p); +#endif + return p; +} + +void *saferealloc(void *ptr, size_t n, size_t size) +{ + void *p; + + if (n > INT_MAX / size) { + p = NULL; + } else { + size *= n; + if (!ptr) { +#ifdef MINEFIELD + p = minefield_c_malloc(size); +#else + p = malloc(size); +#endif + } else { +#ifdef MINEFIELD + p = minefield_c_realloc(ptr, size); +#else + p = realloc(ptr, size); +#endif + } + } + + if (!p) { + char str[200]; +#ifdef MALLOC_LOG + sprintf(str, "Out of memory! (%s:%d, size=%d)", + mlog_file, mlog_line, size); + fprintf(fp, "*** %s\n", str); + fclose(fp); +#else + strcpy(str, "Out of memory!"); +#endif + modalfatalbox(str); + } +#ifdef MALLOC_LOG + if (fp) + fprintf(fp, "realloc(%p,%d) returns %p\n", ptr, size, p); +#endif + return p; +} + +void safefree(void *ptr) +{ + if (ptr) { +#ifdef MALLOC_LOG + if (fp) + fprintf(fp, "free(%p)\n", ptr); +#endif +#ifdef MINEFIELD + minefield_c_free(ptr); +#else + free(ptr); +#endif + } +#ifdef MALLOC_LOG + else if (fp) + fprintf(fp, "freeing null pointer - no action taken\n"); +#endif +} + +/* ---------------------------------------------------------------------- + * Debugging routines. + */ + +#ifdef DEBUG +extern void dputs(char *); /* defined in per-platform *misc.c */ + +void debug_printf(char *fmt, ...) +{ + char *buf; + va_list ap; + + va_start(ap, fmt); + buf = dupvprintf(fmt, ap); + dputs(buf); + sfree(buf); + va_end(ap); +} + + +void debug_memdump(void *buf, int len, int L) +{ + int i; + unsigned char *p = buf; + char foo[17]; + if (L) { + int delta; + debug_printf("\t%d (0x%x) bytes:\n", len, len); + delta = 15 & (unsigned long int) p; + p -= delta; + len += delta; + } + for (; 0 < len; p += 16, len -= 16) { + dputs(" "); + if (L) + debug_printf("%p: ", p); + strcpy(foo, "................"); /* sixteen dots */ + for (i = 0; i < 16 && i < len; ++i) { + if (&p[i] < (unsigned char *) buf) { + dputs(" "); /* 3 spaces */ + foo[i] = ' '; + } else { + debug_printf("%c%02.2x", + &p[i] != (unsigned char *) buf + && i % 4 ? '.' : ' ', p[i] + ); + if (p[i] >= ' ' && p[i] <= '~') + foo[i] = (char) p[i]; + } + } + foo[i] = '\0'; + debug_printf("%*s%s\n", (16 - i) * 3 + 2, "", foo); + } +} + +#endif /* def DEBUG */ + +/* + * Determine whether or not a Conf represents a session which can + * sensibly be launched right now. + */ +int conf_launchable(Conf *conf) +{ + if (conf_get_int(conf, CONF_protocol) == PROT_SERIAL) + return conf_get_str(conf, CONF_serline)[0] != 0; + else + return conf_get_str(conf, CONF_host)[0] != 0; +} + +char const *conf_dest(Conf *conf) +{ + if (conf_get_int(conf, CONF_protocol) == PROT_SERIAL) + return conf_get_str(conf, CONF_serline); + else + return conf_get_str(conf, CONF_host); +} + +#ifndef PLATFORM_HAS_SMEMCLR +/* + * Securely wipe memory. + * + * The actual wiping is no different from what memset would do: the + * point of 'securely' is to try to be sure over-clever compilers + * won't optimise away memsets on variables that are about to be freed + * or go out of scope. See + * https://buildsecurityin.us-cert.gov/bsi-rules/home/g1/771-BSI.html + * + * Some platforms (e.g. Windows) may provide their own version of this + * function. + */ +void smemclr(void *b, size_t n) { + volatile char *vp; + + if (b && n > 0) { + /* + * Zero out the memory. + */ + memset(b, 0, n); + + /* + * Perform a volatile access to the object, forcing the + * compiler to admit that the previous memset was important. + * + * This while loop should in practice run for zero iterations + * (since we know we just zeroed the object out), but in + * theory (as far as the compiler knows) it might range over + * the whole object. (If we had just written, say, '*vp = + * *vp;', a compiler could in principle have 'helpfully' + * optimised the memset into only zeroing out the first byte. + * This should be robust.) + */ + vp = b; + while (*vp) vp++; + } +} +#endif |