Merged gsoc-ssh branch. Closes #910

libssh2/src/pem.c

@@ -0,0 +1,324 @@
+/* Copyright (C) 2007 The Written Word, Inc.
+ * Copyright (C) 2008, Simon Josefsson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms,
+ * with or without modification, are permitted provided
+ * that the following conditions are met:
+ *
+ *   Redistributions of source code must retain the above
+ *   copyright notice, this list of conditions and the
+ *   following disclaimer.
+ *
+ *   Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials
+ *   provided with the distribution.
+ *
+ *   Neither the name of the copyright holder nor the names
+ *   of any other contributors may be used to endorse or
+ *   promote products derived from this software without
+ *   specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ */
+
+#include "libssh2_priv.h"
+
+static int
+readline(char *line, int line_size, FILE * fp)
+{
+    size_t len;
+
+    if (!line) {
+        return -1;
+    }
+    if (!fgets(line, line_size, fp)) {
+        return -1;
+    }
+
+    if (*line) {
+        len = strlen(line);
+        if (len > 0 && line[len - 1] == '\n') {
+            line[len - 1] = '\0';
+        }
+    }
+
+    if (*line) {
+        len = strlen(line);
+        if (len > 0 && line[len - 1] == '\r') {
+            line[len - 1] = '\0';
+        }
+    }
+
+    return 0;
+}
+
+static int
+readline_memory(char *line, size_t line_size,
+                const char *filedata, size_t filedata_len,
+                size_t *filedata_offset)
+{
+    size_t off, len;
+
+    off = *filedata_offset;
+
+    for (len = 0; off + len < filedata_len && len < line_size; len++) {
+        if (filedata[off + len] == '\n' ||
+            filedata[off + len] == '\r') {
+                break;
+        }
+    }
+
+    if (len) {
+        memcpy(line, filedata + off, len);
+        *filedata_offset += len;
+    }
+
+    line[len] = '\0';
+    *filedata_offset += 1;
+
+    return 0;
+}
+
+#define LINE_SIZE 128
+
+int
+_libssh2_pem_parse(LIBSSH2_SESSION * session,
+                   const char *headerbegin,
+                   const char *headerend,
+                   FILE * fp, unsigned char **data, unsigned int *datalen)
+{
+    char line[LINE_SIZE];
+    char *b64data = NULL;
+    unsigned int b64datalen = 0;
+    int ret;
+
+    do {
+        *line = '\0';
+
+        if (readline(line, LINE_SIZE, fp)) {
+            return -1;
+        }
+    }
+    while (strcmp(line, headerbegin) != 0);
+
+    *line = '\0';
+
+    do {
+        if (*line) {
+            char *tmp;
+            size_t linelen;
+
+            linelen = strlen(line);
+            tmp = LIBSSH2_REALLOC(session, b64data, b64datalen + linelen);
+            if (!tmp) {
+                ret = -1;
+                goto out;
+            }
+            memcpy(tmp + b64datalen, line, linelen);
+            b64data = tmp;
+            b64datalen += linelen;
+        }
+
+        *line = '\0';
+
+        if (readline(line, LINE_SIZE, fp)) {
+            ret = -1;
+            goto out;
+        }
+    } while (strcmp(line, headerend) != 0);
+
+    if (!b64data) {
+        return -1;
+    }
+
+    if (libssh2_base64_decode(session, (char**) data, datalen,
+                              b64data, b64datalen)) {
+        ret = -1;
+        goto out;
+    }
+
+    ret = 0;
+  out:
+    if (b64data) {
+        LIBSSH2_FREE(session, b64data);
+    }
+    return ret;
+}
+
+int
+_libssh2_pem_parse_memory(LIBSSH2_SESSION * session,
+                          const char *headerbegin,
+                          const char *headerend,
+                          const char *filedata, size_t filedata_len,
+                          unsigned char **data, unsigned int *datalen)
+{
+    char line[LINE_SIZE];
+    char *b64data = NULL;
+    unsigned int b64datalen = 0;
+    size_t off = 0;
+    int ret;
+
+    do {
+        *line = '\0';
+
+        if (readline_memory(line, LINE_SIZE, filedata, filedata_len, &off)) {
+            return -1;
+        }
+    }
+    while (strcmp(line, headerbegin) != 0);
+
+    *line = '\0';
+
+    do {
+        if (*line) {
+            char *tmp;
+            size_t linelen;
+
+            linelen = strlen(line);
+            tmp = LIBSSH2_REALLOC(session, b64data, b64datalen + linelen);
+            if (!tmp) {
+                ret = -1;
+                goto out;
+            }
+            memcpy(tmp + b64datalen, line, linelen);
+            b64data = tmp;
+            b64datalen += linelen;
+        }
+
+        *line = '\0';
+
+        if (readline_memory(line, LINE_SIZE, filedata, filedata_len, &off)) {
+            ret = -1;
+            goto out;
+        }
+    } while (strcmp(line, headerend) != 0);
+
+    if (!b64data) {
+        return -1;
+    }
+
+    if (libssh2_base64_decode(session, (char**) data, datalen,
+                              b64data, b64datalen)) {
+        ret = -1;
+        goto out;
+    }
+
+    ret = 0;
+  out:
+    if (b64data) {
+        LIBSSH2_FREE(session, b64data);
+    }
+    return ret;
+}
+
+static int
+read_asn1_length(const unsigned char *data,
+                 unsigned int datalen, unsigned int *len)
+{
+    unsigned int lenlen;
+    int nextpos;
+
+    if (datalen < 1) {
+        return -1;
+    }
+    *len = data[0];
+
+    if (*len >= 0x80) {
+        lenlen = *len & 0x7F;
+        *len = data[1];
+        if (1 + lenlen > datalen) {
+            return -1;
+        }
+        if (lenlen > 1) {
+            *len <<= 8;
+            *len |= data[2];
+        }
+    } else {
+        lenlen = 0;
+    }
+
+    nextpos = 1 + lenlen;
+    if (lenlen > 2 || 1 + lenlen + *len > datalen) {
+        return -1;
+    }
+
+    return nextpos;
+}
+
+int
+_libssh2_pem_decode_sequence(unsigned char **data, unsigned int *datalen)
+{
+    unsigned int len;
+    int lenlen;
+
+    if (*datalen < 1) {
+        return -1;
+    }
+
+    if ((*data)[0] != '\x30') {
+        return -1;
+    }
+
+    (*data)++;
+    (*datalen)--;
+
+    lenlen = read_asn1_length(*data, *datalen, &len);
+    if (lenlen < 0 || lenlen + len != *datalen) {
+        return -1;
+    }
+
+    *data += lenlen;
+    *datalen -= lenlen;
+
+    return 0;
+}
+
+int
+_libssh2_pem_decode_integer(unsigned char **data, unsigned int *datalen,
+                            unsigned char **i, unsigned int *ilen)
+{
+    unsigned int len;
+    int lenlen;
+
+    if (*datalen < 1) {
+        return -1;
+    }
+
+    if ((*data)[0] != '\x02') {
+        return -1;
+    }
+
+    (*data)++;
+    (*datalen)--;
+
+    lenlen = read_asn1_length(*data, *datalen, &len);
+    if (lenlen < 0 || lenlen + len > *datalen) {
+        return -1;
+    }
+
+    *data += lenlen;
+    *datalen -= lenlen;
+
+    *i = *data;
+    *ilen = len;
+
+    *data += len;
+    *datalen -= len;
+
+    return 0;
+}